Must, Must not & Need not dễ hiểu nhất (bài tập có giải)

1. Phân biệt Must – Mustn’t – Needn’t

a. Must

Cấu trúc: S + must + Vinf (cần thiết, bắt buộc phải làm gì)

Eg: Don't tell anybody what I said. You must keep it a secret.

(Đừng nói với ai những điều tôi nói nhé. Bạn phải giữ bí mật.)

b. Mustn’t

Cấu trúc: S + mustn’t + Vinf (không được làm gì – chỉ sự cấm đoán)

Eg: You must not make such a noise. The baby is sleeping.

(Bạn không được làm ồn như thế. Đứa trẻ đang ngủ.)

c. Needn’t

Cấu trúc: S + needn’t + Vinf (không cần thiết phải làm gì)

Eg: They are having a day off. They needn’t get up early in the morning.

(Họ đang có một ngày nghỉ. Họ không cần dậy sớm vào buổi sáng.)

2. Cấu trúc tương đương với Needn’t

3. Bài tập Must, Mustn’t, Needn’t

Exercise 1. Điền "mustn't" hoặc "needn't" kết hợp với các động từ dưới đây

0. The window aren't very dirty. You needn't clean them

1. We have a lot of time. We ………………….

2. Keep these documents in a safe place. You ………………… them.

3. I'm not ready yet but you …………… for me. You can go now and I'll come later.

4. We ………………… to turn off the lights before we leave.

5. I …………….. the letter now. I can do it tomorrow.

Exercise 2. Complete the sentences using needn't + the following verbs.

0. We've got plenty of time. We needn't leave yet.

1. I can manage the shopping alone. You .... with me.

2. We .... all the way home. We can get a taxi.

3. Just help yourself if you' d like more to eat. You .... first.

4. We can keep this a secret between ourselves. We .... anybody else.

5. I understand the situation perfectly. You .... further.

Exercise 3. Read the situations and make sentences with needn't have.

0. Paul went out. He took an umbrella because he thought it was going to rain. But it didn't rain.

He needn't have taken an umbrella.

1. Linda bought some eggs when she went shopping. When she got home, she found that she already had plenty of eggs.

She ....................

2. A colleague got angry with you at work. He should at you which you think was unnecessary.

Later you say to him: You ..........................

3. Brian had money problems, so he sold his car. A few days later he won some money in a lottery.

He .......................

4. We took a camcorder with us on holiday, but we didn't use it in the end.

We ........................

5. I thought I was going to miss my train, so I rushed to the station. But the train was late and in the end I had to wait twenty minutes

I ..................................

Exercise 4. Use MUST, MUSTN’T or NEEDN’T

0. I can manage the shopping alone. You needn't come with me.

1. We ………….. walk all the way home. We can get a taxi.

2. Just help yourself if you'd like more to eat. You …………… ask first.

3. We can keep this a secret between ourselves. We …………. tell anybody else.

4. I understand the situation perfectly. You …………… explain further.

5. We have enough food at home, so we …………… go shopping today.

6. Gary gave me a letter post. I …………. remember to post it.

7. Gary give me a letter to post. I …………… forget to post it.

Exercise 5. Fill in each blank with “must” or “mustn't” to complete the following sentences

0. You must stop drinking wine.

1. Students …………. talk in the library.

2. Look! There is an intersection ahead. You ………….. slow down.

3. The sign says ‘No swimming'. We ……………..swim here.

4. We ……………….. hurry or we will be late.

5. The road is very wet and slippery. Drivers ………………. be careful.

Exercise 6. Complete the sentences with must or mustn't

0. You must brush your teeth three times a day.

1. You ……………. forget to do your homework regularly.

2. You ……………. be nice to your classmates.

3. You …………… wear warm clothes when it is cold outside.

4. You ……………. chew gum in class.

5. You …………….. study hard if you want to pass your exams.

6. You ……………… fight with your classmates.

7. You ………………. play football in the classroom.

8. You ………………. listen to your teacher very carefully.

9. You ……………… forget your best friend's birthday.

10. You ……………… be rude to your grandparents.

Xem thêm các bài viết Ngữ pháp Tiếng Anh cực hay với đầy đủ bài tập có đáp án chi tiết khác:

• Have to & Must
• Cách sử dụng Should (I)
• Had better & Cấu trúc It's time
• Cách sử dụng Would
• Lời yêu cầu, Lời mời, lời đề nghị