1. Humus, a substance found in soil, is soft and spongy and enables plant roots to send out tiny hair through that they absorb water and food.

2. From the monitoring of earthquake waves it is evidence that the Earth's outer core is liquid, whereas the inner one is solid.

3. People tend to make a lot of shopping at Xmas time.

4. Stuart stopped to write his letter because he had to leave for the hospital.

5. A fully grown male mountain lion may be eight long feet.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 30 to 34.

The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods.

The second era was initiated in the early decades of the twentieth century and might be called “the vitamin period”. Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of vitamin deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them.

In the third era of nutritional history in the early 1950s to mid-1960s, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.

It can be inferred from the passage that which of the following discoveries was made during the first era in the history of nutrition?

A. Protein was recognized as an essential component of diet. 

B. Vitamins were synthesized from foods. 

C. Effective techniques of weight loss were determined.

D. Certain foods were found to be harmful to good health.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 30 to 34.

The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods.

The second era was initiated in the early decades of the twentieth century and might be called “the vitamin period”. Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of vitamin deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them.

In the third era of nutritional history in the early 1950s to mid-1960s, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.

Why did vitamin therapy begin losing favor in the 1950s?

A. The public lost interest in vitamins. 

B. Medical schools stopped teaching nutritional concepts. 

C. Nutritional research was of poor quality. 

D. Claims for the effectiveness of vitamin therapy were seen to be exaggerated.

Điền từ phù hợp từ 1 - 10

Many people nowadays have to ----(1) false teeth when they are ----(2). The reason is that tooth ----(3) increases a lot. The amount of ----(4) in our food also increases. Doctors and dentists now know that sugar is the chief ----(5) of tooth decay. Eskimos's ----(6), for example, started to decay when they began to ----(7) sweeter food.
Long ago dectors did not like to ----(8) people's teeth. Barbers and Blacksmiths looked after people's teeth and ----(9) them out when thay decayed. Some people -----(10) toothache was punishment from the gods.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 30 to 34.

Vitamins, taken in tiny doses, are a major group of organic compounds that regulate the mechanisms by which the body converts food into energy. They should not be confused with minerals, which are inorganic in their makeup. Although in general the naming of vitamins followed the alphabetical order of their identification, the nomenclature of individual substances may appear to be somewhat random and disorganized.. Among the 13 vitamins known today, five are produced in the body. Because the body produces sufficient quantities of some but not all vitamins, they must be supplemented in the daily diet. Although each vitamin has its specific designation and cannot be replaced by another compound, a lack of one vitamin can interfere with the processing of another. When a lack of even one vitamin in a diet is continual, a vitamin deficiency may result.

The best way for an individual to ensure a necessary supply of vitamins is to maintain a balanced diet that includes a variety of foods and provides adequate quantities of all the compounds. Some people take vitamin supplements, predominantly in the form of tablets. The vitamins in such supplements are equivalent to those in food, but an adult who maintains a balanced diet does not need a daily supplement. The ingestion of supplements is recommended only to correct an existing deficiency due to unbalanced diet, to provide vitamins known to be lacking in a restricted diet, or to act as a therapeutic measure in medical treatment. Specifically, caution must be exercised with fat-soluble substances, such as vitamins A and D, because, taken in gigantic doses, they may present a serious health hazard over a period of time

It can be inferred from the passage that vitamin supplements can be advisable ________. 

A. in special medical cases

B. in most restricted diets

C. after correcting a dietary deficiency

D. before beginning a therapeutic treatment