II. Read the following passage and fill in the gaps with one suitable word ( 5p) What is the truth about light wave theory? ……56……. many years, scientists were in disagreement. Newton hypothesized tha...

II. Read the following passage and fill in the gaps with one suitable word ( 5p) What is the truth about light wave theo...

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Corn dog

28 tháng 7 2017 lúc 22:28

Nowadays in the news you can read a lot about biotechnology and the controversies about it and perhaps you ask yourself what it is exactly. Well, this article is going to give you a brief history of the field of biotechnology and show you that, although the word “biotechnology” was first used in 1919, we have been using biotechnology for many thousands of years in ways that are completely uncontroversial. It will also look at the more modern developments which have started intense debate....

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Nowadays in the news you can read a lot about biotechnology and the controversies about it and perhaps you ask yourself what it is exactly. Well, this article is going to give you a brief history of the field of biotechnology and show you that, although the word “biotechnology” was first used in 1919, we have been using biotechnology for many thousands of years in ways that are completely uncontroversial. It will also look at the more modern developments which have started intense debate. When you are drinking a cold beer on a hot day, or eating a delicious cheese sandwich, you can thank biotechnology for the pleasure you are experiencing. That’s right! Beer, bread and cheese are all produced using biotechnology. Perhaps a definition will be useful to understand how. A standard definition is that biotechnology (or biotech for short) is the application of science and engineering to the direct or indirect use of living organisms. And as you know, the food and drink above are all produced by the fermentation of micro-organisms. In beer, the yeast multiplies as it eats the sugars in the mixture and turns them into alcohol and CO2. This ancient technique was first used in Egypt to make bread and wine around 4000BC! Antibiotics are used to prevent and treat diseases, especially those caused by bacteria. They are natural substances that are created by bacteria and fungi. The first antibiotic was made in China in about 500BC – to cure boils. In 1928 Alexander Fleming discovered penicillin and it was considered a medical miracle. Modern research is looking at the creation of super-antibodies which can kill bacteria and viruses inside the cells that house them. Our modern consumer society produces a lot of waste which needs to be disposed of safely and without harmful end products. Environmental biotechnology can help. Indeed, the use of bacteria to treat sewage was first practiced in 1914 in Manchester, England. Vermiculture or using worms to treat waste is another environmentally-friendly practice and the end product is a natural fertiliser. Bacteria have even been developed to help with problems such as oil spills. They convert crude oil and gasoline into non-toxic substances such as carbon dioxide, water and oxygen and help create a cleaner, healthier environment. These examples of biotechnology are accepted by most people. However, the discovery of the DNA structure by Watson and Crick in 1953 was the beginning of the modern era of genetics and the following areas of biotech are very controversial. Read on… The genetic modification of plants and crops has been in practice for many years. This involves changing the genetic code of these plants so that they are more resistant to bad conditions like drought, floods and frost. Supporters of GM food say that it can offer the consumer better quality, safety and taste and for over a decade Americans have been eating GM food. However, things are very different in Europe where genetically modified food is very strictly regulated and regarded with deep suspicion by the public. GM food has even been called “Frankenfood” in the press, a term inspired by the novel Frankenstein by Mary Shelley. There is a great cultural divide between America and Europe over whether such food is safe to eat and will not harm the environment and the discussion is still in progress. 1997 saw the birth of Dolly the sheep, the first animal cloned from an adult cell. This was a remarkable achievement which created world-wide debate on the ethical issues surrounding cloning. International organisations such as the European parliament, UNESCO and WHO all declared that human cloning is both morally and legally wrong. However, we need to make a distinction between reproductive cloning and therapeutic cloning. Nowadays the idea of reproductive cloning – creating a copy of another person - is no longer interesting for researchers. Instead therapeutic cloning is creating excitement in the biotech world. Key to this technique is stem cells, which are master cells that have the potential to become any other kind of cell in the body e.g. nerve cells, blood, heart muscle or even brain cells. Stem cells themselves have generated a lot of controversy as it was believed that only human embryos could provide them. However, it now appears that adult stem cells offer the same possibility. This would mean that a patient who suffered a heart attack could provide doctors with his adult stem cells which could then be implanted back into his heart and used to create heart muscle, replacing the muscle that was damaged. As the genetic code is identical, there would be no problem of the body rejecting the implant as, unfortunately, happens with organ transplants. In the future, biotechnologists hope that stem cells could be used to grow entire organs. In this way biotechnology offers the hope of revolutionising medical treatment. In this brief overview of the history of biotechnology we have jumped from making bread to making human organs - an enormous leap- and it is clear that these modern practices raise many controversial issues. However, despite the debate, we can imagine that as biotechnology has been around for many years, it will still be around for some time to come - but who knows where it will take us? Questions: After reading, choose the best answer for the following questions 1. What is the main topic of the article? Brief history and modern developments of biotechnology Benefit of biotechnology Modern research in biotechnology 2. What does the pronoun "IT" in the first paragraph refer to? Biotechnology The article The word "Biotechnology" 3. Which products were first made with fermentation of micro-organisms? Beer, bread and cheese Bread and wine Beer and cheese Decide whether the statement below is True or False. 4. Alexander Fleming discovered super-antibodies which can kill bacteria and viruses inside the cells that house them. TrueFalse 5. GM food is easily available in the U.S. and Europe. TrueFalse 6.Researchers believe that adult stem cells could be used to create body parts. TrueFalse

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Nguyễn Đỗ ánh

22 tháng 1 2018 lúc 12:37

The weather is not beautiful all of the time. Perhaps you can remember a day when bad weather made you afraid. One kind of bad weather that scares many people is called a thunderstorm. This is what happens when there is a thunderstorm. First, you see a sudden flash of bright light. A few seconds later you hear a loud rumbling sound. This quick flash is called lightning and the loud sound is called thunder. Lightning is colorful , but it can cause serious problems. Lightning is electricity th...

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The weather is not beautiful all of the time. Perhaps you can remember a day when bad weather made you afraid. One kind of bad weather that scares many people is called a thunderstorm. This is what happens when there is a thunderstorm. First, you see a sudden flash of bright light. A few seconds later you hear a loud rumbling sound. This quick flash is called lightning and the loud sound is called thunder. Lightning is colorful , but it can cause serious problems. Lightning is electricity that is moving very rapidly. It may be moving between a cloud and the ground, between two clouds, or between two parts of the same cloud. The lightning heats the air around it. This hot air expands, or get bigger, and it causes the air to move in waves. The air waves pass you in a series, one after another. For this reason, you may hear many rumbles and not just one sound.

____ 29/ Lightning may move between a cloud and the ground.

____ 30/ Thunder is a very bright light in a thunderstorm.

____ 31/ When you hear thunder you may hear a series of loud sounds and not one

big sound. This is because the air waves pass one after another.

____ 32/ Lightning always moves rapidly.

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Thanh Huyền Trịnh

25 tháng 3 2018 lúc 21:41

Supply the corect form of the words in brackets:

1. That boy has a (girl).... face.

2. We'd like to test the truth or (false).... of her claims.

3. Even after thirty years living in the countryside, I fear I am not a proper (country)....

4. The office was light and (air)....

5. He is British football's most (market).... commodity

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Triệu Thiên Minh

31 tháng 5 2020 lúc 21:09

Section III. Read the following passage and choose the suitable word to fill in the blank easily happen drops sweets shock themselves with way because accidents anything dangerous catches control them children Many thousands of children have accidents in their homes. As a result, some children die. The most comm...

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Section III. Read the following passage and choose the suitable word to fill in the blank

easily happen drops sweets shock themselves with way

because accidents anything dangerous catches control them children

Many thousands of children have accidents in their homes. As a result, some children die. The most common .................... (1) are with fire and hot water. Small children often touch pots of boiling water on the stove. The pots fall over and the hot water falls on the children and burns .................... (2) Some children like to play .................... (3) fire. They enjoy striking matches or throwing things on a fire to make it burn brightly. If a fire gets too big, it gets out of .................... (4). Then the house .................... (5) fire. It is very .................... (6) to play with matches. When a child strikes a match, the flame soon burns near his fingers. Then he .................... (7) the match on the floor. Many houses catch fire in this .................... (8)

Some kinds of clothing burn very .................... (9). Many .................... (10) have been badly burned because they have stood near a fire and their clothing has suddenly caught fire.

Although fire and hot water cause most accidents in the home, many children cut .................... (11) with knives. Others get an electric .................... (12). Some children are made very ill from taking their parents’ medicine. Many small children have to go to hospital every year because they thought a box of medicine was a box of .................... (13).

There is only one good way to see to it so that accidents do not .................... (14) in the home: do not touch .................... (15) that is dangerous.

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Maicute

14 tháng 11 2017 lúc 12:15

I- Choose the correct answer from the four options given( marked A, B, C or D) to complete the following sentences. 1. Lan always talks too much about nothing . She is ....................................... A out going B talkative C naughty D sociable 2. It is not ................ to see any thing in the room. A light enough B very light C too light D enough light 3 Look! There are dark clouds coming. It .................................

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I- Choose the correct answer from the four options given( marked A, B, C or D) to complete the following sentences.

1. Lan always talks too much about nothing . She is .......................................

A out going B talkative C naughty D sociable

2. It is not ................ to see any thing in the room.

A light enough B very light C too light D enough light

3 Look! There are dark clouds coming. It ................................................

A will rain B would rain C is going to rain D rains

4. I'm sorry that the manager is out at the moment . Would you like to ...... a massage?

A leave B give C take D get

5. Remember ....................any one about my mistakes.

A not telling B not tell C not to tell D don't tell

6. The girl is standing in the room, ....................in the mirror.

A to look at herself B looking into herself

C looking after D looking at herself

7. We............... each other since we ................goodbye.

A haven't met/ say B didn't meet/ said

C haven't met/ said D don't meet/ said

8. People used to travel around...............but now they go by cars or motorbikes

A on foot B with foot C in foot D on their foot

9. The meal will be served ........................about ten minutes.

A in B on C for D at

10 Have you made up your................. to buy a new house yet?

A soul B heart C mind D head

11 The blue coat isn't so expensive .................the red one.

A as B than C like D by

12. We should keep the windows open ..........................fresh air can get in.

A so that B so as to C in order D so as that

13 Plastic bags are difficult to be dissolved , so the amount of garbage will..................

A reduce B increase C develop D decrease

14. What is the price of the printer................. in the USA ?

A is making B is made C that made D made

15. Don't worry . We...........................of the test result next week.

A will inform B will be informed C are informing D are informed

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Tran Dung

12 tháng 6 2020 lúc 8:46

I. Put in the correct verb form: 1. The thieves (run) away when the police (arrive) yesterday. 2. Millions of junk emails (receive) in Vietnam every day. 3. Ann isn’t answering the phone. I think I (send) her a message. 4. If you (leave) butter on the top of a hot potato dish, it (melt). 5. What you (do) if you (be) the mayor of the city? II. Fill in each gap with a suitable word only. W. Shakespeare is probably the (6) … famous playwright of all time. It is therefore quite surprisin...

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I. Put in the correct verb form: 1. The thieves (run) away when the police (arrive) yesterday. 2. Millions of junk emails (receive) in Vietnam every day. 3. Ann isn’t answering the phone. I think I (send) her a message. 4. If you (leave) butter on the top of a hot potato dish, it (melt). 5. What you (do) if you (be) the mayor of the city? II. Fill in each gap with a suitable word only. W. Shakespeare is probably the (6) … famous playwright of all time. It is therefore quite surprising that little is (7) …about his life. There is a period (8) … 1586 and 1592 which is a complete mystery even today. Was he a teacher in Wales, a travelling actor or perhaps a spy (9) … these years? A new Spanish film may (10) … another theory to the existing ones. He (10) … left their wives at that period and the film offers a romantic reason too - a Spanish actress (11) ... Leonor that he is believed to be (12)…. love. The other interesting fact is (13)…..change of writing style in both fictions. After 1592, Shakespeare started (14) … tragedies & Cervantes created Don Quixote. Perhaps the (15) …will never be known but the film gives us an entertaining look at the past. III. Correct the mistakes 16. She was so an intelligent student that she could pass the final exam easily. ................................................................................................................................ 17. They used to operating these machines by hand. ............................................................................................................................... 18. My cousin learnt to play the piano since he was only 4 years old. ............................................................................................................................... 19. Rose isn’t enough tall to become a professional model. ............................................................................................................................... 20. They did not meet each other since they left school more than five years ago. ...............................................................................................................................

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Như Phạm

26 tháng 12 2017 lúc 18:56

I. Give advice with ought to or ought not to. Minh looks very tired. (go to bed late) My parents are going to visit France. (learn a few French words) It’s eight o’clock. Helen is still sleeping. (get up earlier) There is traffic jam and the people are rushing forward. (drive like that) Nam is going to have final exam tomorrow morning. He is playing computer games now. (play computer games – learn the lessons) The speed limit is 30 mph, but Catherine is driving 50 mph. (drive so fast) The street...

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I. Give advice with ought to or ought not to.
Minh looks very tired. (go to bed late)
My parents are going to visit France. (learn a few French words)
It’s eight o’clock. Helen is still sleeping. (get up earlier)
There is traffic jam and the people are rushing forward. (drive like that)
Nam is going to have final exam tomorrow morning. He is playing computer games now. (play computer games – learn the lessons)
The speed limit is 30 mph, but Catherine is driving 50 mph. (drive so fast)
The street is too narrow. It’s always full of vehicles. (they/ widen this street)
I’m bored. I need a change. (go away for a few days)
II. Fill in each blank with a correct reflexive pronoun.
My sister often looks at _______ in the mirror.
Mark made _______ a sandwich.
This refrigerator defrosts _______.
Hoa and I ________ saw that accident yesterday.
Did you pay for _______?
The children can look after _______ for a few days.
Please help me. I can’t do it ________.
Take care of _________?
He was very surprised when he looked _______ in the mirror.
I don’t like going to the cinema with other people. I prefer going by _______.
The child had no bothers or sisters, so she often had to play by _______.
I’m afraid that the children are going to cut ________ on the broken glass.
We had a great time in London together. We really enjoyed ________.
“Can I take another biscuit?” – Of course. Help _________”.
Don’t worry about Linh and me. We can look after _________.
I gave them a key to our house so that they could let ________ in.
Phuong had a great holiday. She enjoyed __________.
Please try and understand how I feel. Put __________ in my position.
I taught _______ to play the guitar. I have never had lessons.
An elephant hurt _______ when it tried to get out of the zoo yesterday.
I don’t need any help. I can take care of _______.
Sarah and I didn’t enjoy _______ at the disco last night.
This exercise isn’to very difficult. Do it _______.
My brother can repair the bicycle _______.
III. Read the text and answer the following questions.
Peter had a letter form his sister yesterday. She lives in Nigeria. In her letter, she said that she was coming to England next month. If she comes, she will get a surprise. Peter is now living in a beautiful new house in the country. Work on it had begun before his sister left. The house was completed five months ago. In his letter, he said that, he wanted her to stay with his family. The house has many large rooms and there is a lovely garden. It is a modern house. So it looks strange to some people. It must be the only modern house in the district.
Where does Peter’s sister live?
What is she going to do next month?
Where is Peter living now?
When was the house completed?
Has it got many large rooms and a lovely garden?
Did he invite his sister to stay with him?
Why does the house look strange to some people?
VI. Fill in each blank with a suitable word to complete the following passage.
If you see a fire, you should ring the school bell ____ (1) one minutes. When they ____ (2) the bell, students should quickly leave ____ (3) classroom. The monitor should take the register with him on leaving the classroom. The _____ (4) should line up outside the classroom as soon _____ (5) everyone has left the room. Then _____ (6) class should walk quickly along the path to the main entrance. When they _____ (7) the main entrance, the students should stand quietly in the playground. While they ______ (8) waiting there, one of the students ______ (9) look for the class teacher in the playground. On finding _____ (10), he should give him the class register.

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Hiền Cherry

16 tháng 7 2018 lúc 11:32

Read the following passage and choose the most appropriate answer from A,B,C or D to answer questions. Human memory, formerly believed to be rather inefficient, is really more sophisticated than that of a computer. Researchers approaching the problem from a variety of points of view have all concluded that there is a great deal more stored in our minds than has been generally supposed. Dr. Wilder Penfield, a Canadian neurosurgeon, proved that by stimulating their brains electrically, he could e...

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Read the following passage and choose the most appropriate answer from A,B,C or D to answer questions.
Human memory, formerly believed to be rather inefficient, is really more sophisticated than that of a computer. Researchers approaching the problem from a variety of points of view have all concluded that there is a great deal more stored in our minds than has been generally supposed. Dr. Wilder Penfield, a Canadian neurosurgeon, proved that by stimulating their brains electrically, he could elicit the total recall of specific events in his subjects’ lives. Even dreams and other minor events supposedly forgotten for many years suddenly emerged in detail.

Although the physical basis for memory is not yet understood, one theory is that the fantastic capacity for storage in the brain is the result of an almost unlimited combination of interconnections between brain cells, stimulated by patterns of activity. Repeated references to the same information support recall. Or, to say that another way, improved performance is the result of strengthening the chemical bonds in the memory.

1. With what topic is the passage mainly concerned?

A. Wilder Penfield B. Neurosurgery

C. Human memory D. Chemical reactions

2. According to the passage, researchers have concluded that

A. the mind has a much greater capacity for memory than was previously believed.

B. the physical basis for memory is clear.

C. different points of view are valuable.

D. human memory is inefficient.

3. How did Penfield elicit dreams and other minor events from the past?

A. By surgery B. By electric stimulation C. By repetition D. By chemical stimulation

4. According to the passage, the capacity for storage in the brain

A. can be understood by examining the physiology.

B. is stimulated by patterns of activity.

C. has a limited combination of relationships.

D. is not influenced by repetition.

5. The word “bonds” in the last line means

A. promises. B. agreements. C. connections. D. responsibilities

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Corn dog

28 tháng 7 2017 lúc 21:15

Read the passage then answer the following questions: I will think of it.It is easy to say this; but do you know what great things have come from thinking? We can not see our thouhts, or hear, or taste, or feel them;and yet what mighty power they have! Sir Isac Newton was seated in his garden on a summers evning, when he saw an appe fall from a tree. He began to think, and, in trying to find out why the apple fell, discoveed how the earth, sun, moon, and stars are kept in their places. A boy na...

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Read the passage then answer the following questions:

"I will think of it."It is easy to say this; but do you know what great things have come from thinking? We can not see our thouhts, or hear, or taste, or feel them;and yet what mighty power they have! Sir Isac Newton was seated in his garden on a summer's evning, when he saw an appe fall from a tree. He began to think, and, in trying to find out why the apple fell, discoveed how the earth, sun, moon, and stars are kept in their places. A boy named James Watt sat quitly by the firside, watching the lid of the tea kette as it moved up and down. He began to think; he wanted to find out why the steam in the kettle moved the heavy lid. From that time he went on thinking and thinking; and when he became a man, he improved the steam engine so much that it could, with the greatest ease, do the work of many horses. When you see a steamboat, a steam mill, or alocomotive, remember that it would never have been built if it had not been for the hard thinking of someone. A man named Galileo was once standing in the cathedral of Pisa, when he saw a chandelier swaying to and fro. This set him thinking, and it led to the invention of thependulum. James Ferguson was a poor Scotch shepherd boy. Once, seeing the inside of a watch, he was filled with wonder. "Why should I not make a watch?" thought he. But how was he to get the materials out of which to make the wheels and the mainspring? He soon found how to get them: he made the mainspring out of a piece of whalebone. He then made a wooden clock which kept good time. He began, also, to copy pictures with a pen, and portraits with oil colors. In a few years, while still a small boy, he earned money enough to support his father. When he became a man, he went to London to live. Some of the wisest men in England, and the king himself, used to attend his lectures. His motto was, "I will think of it;" and he made his thoughts useful to himself and the world.When you have a difficult lesson to learn, don't feel discouraged, and ask someone to help you before helping yourselves.Think, and by thinking you will learn how to think to some purpose.

1. What is the main idea of this passage?

A/Great geniuses didn't have to think.

B/We should always think.

C/Isaac Newton was a thinker.

D/Galileo was a thinker.

2. What caused Galileo to invent the pendulum?

A/Seeing a cathedral.

B/Thinking about apples.

C/Seeing a chandelier swing and thinking.

D/Thinking about gravity.

3. Why did the king attend James Ferguson's lectures?

A/Because Ferguson taught about pendulums. B/Because Ferguson was a brilliant thinker. C/Because the king was jealous of Ferguson's intelligence. D/Because Ferguson was an entertaining speaker. 4.How is Galileo similar to Isaac Newton?

AThey were born at the same time. BThey have nothing in common. CThey are both great thinkers. DThey both discovered gravity. 5.Why did James Ferguson decide to make a watch?

A/Because he was curious after seeing the inside of a watch. B/Because the king asked him to. C/Because he needed to support his sick father and mother. D/Because he was poor and needed the money.

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Lớp 12 Tiếng anh Luyện tập tổng hợp

Luyện tập tổng hợp

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