III. Choose the best option marked A, B, C or D to complete each sentence.
1. When I have the whole free day, I prefer________ to the outskirts to staying in the city.
A. going B. to go C. go D. went
2. Last night, she had an________ dancing performance in the school festival.
A. ador B. adoring C. adored D. adorable
3. I am very impressed with sarong – a traditional________of the Khmer people.
A. custom B. clothing C. clothes D. costume
4. The life in this remote area has become less _______ since they had electricity.
A. convenient B. convenience C. inconvenient D. inconveniently
5. She is driving too slowly, so I think she will get there________than us.
A. more late B. later C. more lately D. latelier
6. My father sometimes goes________in the forests. He’d like to find some more food for our family.
A. hunt B. hunting C. to hunt D. hunted
7. Look! Some children are________the buffaloes.
A. picking B. herding C. driving D. playing
8. Is living in the city________than living in the country?
A. more convenient B. as convenient
C. most convenient D. so convenient
9. He is surprised ________that there are 54 ethnic groups in our country.
A. to understand B. to study C. to know D. find
10. Do you think friendship on the internet is __________?
A. cultural B. satisfied C. addicted D. virtual
11. The Gong Festival is held ________ in the Central Highlands.
A. yearly B. annually C. year D. annual
12. The Viet (or Kinh) have________number of people, account for about 86% of the population.
A. large B. the large C. larger D. the largest
13. ________ ethnic group has a larger population, the Tay or the Ede?
A. What B. Which C. Why D. Who
14. I love the_______sky on starry nights. It looks fantastic.
A. safe B. quiet C. slow D. vast
15. Our team won the games because we play________.
A. good B. Well C. bad D. badly
16. The farmers said that they had a poor_________ because of the lack of water.
A. pasture B. harvest C. house D. town

17. It is dangerous to let children _______in the kitchen.
A. to play B. playing C. play D. played
18. Linh _______to visit me next week.
A. is going B. going to C. is going to D. are going to
19. ________ does Miss Hoa want to be a teacher? -Because she loves children.
A.What B. Who C. What D. Why
20. We found the film_______because of the excellent actors and actresses.
A. interest B. interested C. interesting D. interests
21. The_______have a very hard life. They cannot live permanently in one place.
A. nomads B. nomadic C. farmers D. workers
22. His parents feel very sad and upset because he’s_______ to computer games.
A. addiction B. addicted C. addictive D. addict
23. Mongolian children start to learn________before they can walk.
A. horse riding B. riding horse C. ride horse D. horse ridden
24. I would love_________ them again.
A. see B. to see C. seeing D. to seeing
25. The crops ___________ on the weather.
A. depend heavy B. depend heavily C. affect heavy D. affect heavily

III. Complete the sentences, using “have to” and the verbs from the box in the correct form either
open, talk, stop, take, decide,  get up, send, explain
20. We____________ talking when the lesson starts. (positive)
21. We ____________ early at the weekends. (negative)
22. I ____________ which job I want before the end of the week. (positive)
23. We____________ the bus into the city center. We can walk. (negative)
24. She____________ the shop at 9 o’clock every morning. (positive)
25. You ____________ quietly in the library. (positive)
26. You____________ the letter to him by post. I will see him tomorrow and I can give it to him then.(negative)

VII. Rewrite the sentences using “should/ shouldn’t”.
47. Don’t touch this switch.
This switch _______________________________________
48. It isn’t a good idea for you to put so much salt in the soup.
You ____________________________________________
49. It isn’t a good idea for you to drink so much alcohol.
You_____________________________________________
50. You can’t park here because it’s a restricted area.
You ____________________________________________

III. Complete the sentences with a form of “have to” or “should”. Make the verbs negative when
necessary.
20. You __________come with me if you don’t want to. I’ll go on my own.
21. If you need some help with your homework, you __________ go to the library.
22. If you have a ticket, you __________queue. You can go straight in.
23. You __________tell lies. It’s wrong.
24. Tuan works too much. I think he __________take it easy.
25. Your hair’s too long. I think you__________ get it cut.
26. Your clothes are dirty. You __________wash them.
27. I’m going to bed. I __________ get up early tomorrow.
28. I’d like to meet your best friend. You __________invite him/ her round.

6. Cross out the right part in the following sentences.
1. You don't have to/ must eat anything you don't like.
2. If you don't want to have a sore throat, you don't have to/ shouldn’t drink too much iced water.
3. Flight attendants have to/ mustn't take care of passengers on the plane.
4. During the lesson, students don't have to/ mustn't leave class without the teacher's permission.
5. Her mother cooks for her, so she herself doesn't have to/mustn't cook.
6. Smokers don't have to/ mustn't smoke in public places. This is stated in a new law.
7. Drinks are free for today. It means that you don't have to/mustn't pay money for drinks today.

8. Cuong won the lottery last year, so he doesn't have to/mustn't work now.
9. According to the company regulations, staff have to/ must finish their work with highest
efficiency.
10. To be healthy, we mustn't/ should eat healthful food and do the exercise regularly.

5. Complete the sentences with must/ mustn't or have/has to/ don't/doesn't have to
1. You___________ study harder to get better marks
2. The boy is only twelve years old. He___________ ride a motorbike.
3. You___________worry about me! I am ok now.
4. All the students___________ obey the school rules.
5. You___________ be impolite to elderly people.
5. Secretaries___________ answer the phone. That is a part of their job.
7. Hoang and My are on holiday. They___________ go to school today
8. He___________ come if he doesn't want to join with us.
9. My classmate is very ill. She___________ see a doctor as soon as possible.
10. Your hands are dirty. You ___________ wash them before meal.
11. We___________ brush our teeth at least once a day.
12. I___________ take these books back to the school library on time or I will get a fine.
13. Children___________ play with dangerous objects like knives and matches.
14. Students___________ use mobile phones during the test.
15. Today she doesn't have the literature lesson, so she___________bring her literature book.
16. Babies___________ go to bed early.
17. There is a lift in this building, so we___________ climb the stairs.
18. Huong doesn't like her new job. Sometimes she___________ work at weekends.

6. Điền động từ khuyết thiếu “mustn’t” hoặc “don’t have to“ vào chỗ trống.
1. You _____________pick me up tomorrow. I will take a taxi.
2. Look at that sign! You__________ walk on the grass.
3. You__________ blame anyone for your mistakes. You need to be responsible for yourself.
4. You__________ be absent from class tomorrow because the teacher will check your attendance.
5. I _________ prepare dinner because we will eat out tonight.
6. You _________ leave any rubbish here. It is forbidden.
7. You __________ let anyone know that. It is a big secret.
8. You __________ come early tomorrow because the event will start late.
9. You __________ park your car here. There is a ”No parking sign.”
10. We don’t have much money left. We ___________ waste anymore.
11. They __________ forget their homework at home.
12. I ___________ do the housework because I have a maid do it for me.
13. They_________ break the rule that way. It is unacceptable.
14. I _________ use the computer after 11 pm because my mother doesn’t allow me to.
15. You __________ buy that book. I will lend you mine.

3. Chuyển những câu sau thành câu đưa ra lời khuyên với “should” hoặc “shouldn’t”.
1. You pay more attention to what your parents say.
__________________________________________________________
2. Everyone goes home for a family reunion regularly.
__________________________________________________________
3. You travel more to broaden your horizon.
__________________________________________________________
4. What does Hoang do to study better?
__________________________________________________________
5. We don’t go on our vacation because it’s very far from our location.
__________________________________________________________
6. They are never rude to other people.
__________________________________________________________

Giải giúp mình vs ạ, mấy bn giải chi tiết giúp mình vs ạ

x² + 6x - y² + 9