English grammar worksheet for B1 level students practicing modal verbs: CAN, CAN'T, COULD, COULDN'T, MUST, and MUSTN'T.

To solve this worksheet, we need to fill in the blanks with the appropriate modal verbs (`CAN`, `CAN'T`, `COULD`, `COULDN'T`, `MUST`, or `MUSTN'T`) based on the context of each sentence. Let's go through each sentence step by step:

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1. She is a small baby. She _______ eat meat, but she _______ drink milk.

- A small baby cannot eat meat because it is too difficult for them to chew and digest.
- However, a baby can drink milk as it is suitable for their diet.
- Answer: She can't eat meat, but she can drink milk.

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2. He is so ill that he _______ see the doctor.

- If someone is very ill, they must see a doctor to get medical help.
- Answer: He is so ill that he must see the doctor.

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3. It's raining heavily. You _______ take your own umbrella.

- In heavy rain, it is necessary to take an umbrella to stay dry.
- Answer: You must take your own umbrella.

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4. We _______ pick the flowers in the park. It's forbidden.

- Since picking flowers in the park is forbidden, it is not allowed.
- Answer: We mustn't pick the flowers in the park.

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5. I _______ sing now but I _______ sing very well when I was a child.

- The speaker might not be able to sing well now, but they could sing well when they were a child.
- Answer: I can't sing now but I could sing very well when I was a child.

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6. Mike is only nine months old. He _______ eat nuts yet.

- A nine-month-old baby is too young to eat nuts, as they are a choking hazard.
- Answer: Mike is only nine months old. He can't eat nuts yet.

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7. He has a lot of weight so he _______ run so fast.

- Someone who is overweight may not be able to run as fast due to physical limitations.
- Answer: He has a lot of weight so he can't run so fast.

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8. I'm very tall, so I _______ play basketball.

- Being tall is an advantage in playing basketball, so the person can play it.
- Answer: I'm very tall, so I can play basketball.

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9. You _______ park that car there. It's a no-parking zone.

- Parking in a no-parking zone is not allowed.
- Answer: You mustn't park that car there.

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10. Many students in Great Britain _______ wear a uniform when they go to school.

- In many schools in Great Britain, students are required to wear uniforms.
- Answer: Many students in Great Britain must wear a uniform when they go to school.

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11. George has travelled a lot. He _______ speak 4 languages.

- Given that George has traveled a lot, it is reasonable to assume he can speak multiple languages.
- Answer: George has travelled a lot. He can speak 4 languages.

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12. I _______ come with you now because I'm studying for my test.

- The person cannot come with the other person because they are busy studying.
- Answer: I can't come with you now because I'm studying for my test.

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13. Footballers _______ touch the ball with their hands.

- In football (soccer), players are not allowed to touch the ball with their hands (except for the goalkeeper).
- Answer: Footballers mustn't touch the ball with their hands.

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14. _______ I use your phone?

- This is a question asking for permission to use someone's phone.
- Answer: Can I use your phone?

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15. I'm sorry I _______ come yesterday. I had to work late.

- The person couldn't come yesterday because they had to work late.
- Answer: I'm sorry I couldn't come yesterday. I had to work late.

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16. You _______ speed through the city. It's dangerous!

- Speeding through the city is dangerous and should not be done.
- Answer: You mustn't speed through the city. It's dangerous!

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17. You have been coughing a lot recently. You _______ smoke so much.

- Smoking excessively can cause health issues like coughing, so it is advised against.
- Answer: You have been coughing a lot recently. You mustn't smoke so much.

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18. I'm very tired today. I _______ clean my room now, but I'll do it tomorrow.

- The person is too tired to clean their room today, so they cannot do it now.
- Answer: I'm very tired today. I can't clean my room now, but I'll do it tomorrow.

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19. I _______ eat lasagne when I was a child, but I like it today.

- The person did not like lasagne as a child but now enjoys it.
- Answer: I couldn't eat lasagne when I was a child, but I like it today.

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20. We _______ go to the bank today. We haven't got any money left.

- Without money, there is no need to go to the bank.
- Answer: We can't go to the bank today. We haven't got any money left.

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21. You _______ sleep in that room. It's full of boxes and other stuff.

- The room is cluttered and not suitable for sleeping.
- Answer: You mustn't sleep in that room. It's full of boxes and other stuff.

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22. I _______ swim very far these days, but ten years ago, I _______ swim over to the other side of the lake.

- The person cannot swim very far now but could swim farther in the past.
- Answer: I can't swim very far these days, but ten years ago, I could swim over to the other side of the lake.

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23. You have a bad headache, so you _______ go to bed earlier.

- Having a bad headache suggests the person should rest early.
- Answer: You have a bad headache, so you must go to bed earlier.

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24. I _______ feed the baby now, so can you do it for me?

- The person cannot feed the baby at the moment and needs help.
- Answer: I can't feed the baby now, so can you do it for me?

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25. Tourists _______ take their passports with them when they go abroad.

- Tourists are required to carry their passports when traveling abroad.
- Answer: Tourists must take their passports with them when they go abroad.

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Final Answers:

1. She can't eat meat, but she can drink milk.
2. He is so ill that he must see the doctor.
3. You must take your own umbrella.
4. We mustn't pick the flowers in the park.
5. I can't sing now but I could sing very well when I was a child.
6. Mike is only nine months old. He can't eat nuts yet.
7. He has a lot of weight so he can't run so fast.
8. I'm very tall, so I can play basketball.
9. You mustn't park that car there.
10. Many students in Great Britain must wear a uniform when they go to school.
11. George has travelled a lot. He can speak 4 languages.
12. I can't come with you now because I'm studying for my test.
13. Footballers mustn't touch the ball with their hands.
14. Can I use your phone?
15. I'm sorry I couldn't come yesterday. I had to work late.
16. You mustn't speed through the city. It's dangerous!
17. You have been coughing a lot recently. You mustn't smoke so much.
18. I'm very tired today. I can't clean my room now, but I'll do it tomorrow.
19. I couldn't eat lasagne when I was a child, but I like it today.
20. We can't go to the bank today. We haven't got any money left.
21. You mustn't sleep in that room. It's full of boxes and other stuff.
22. I can't swim very far these days, but ten years ago, I could swim over to the other side of the lake.
23. You have a bad headache, so you must go to bed earlier.
24. I can't feed the baby now, so can you do it for me?
25. Tourists must take their passports with them when they go abroad.

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Boxed Final Answer:

\boxed{
\begin{aligned}
&1. \text{can't}, \text{can} \\
&2. \text{must} \\
&3. \text{must} \\
&4. \text{mustn't} \\
&5. \text{can't}, \text{could} \\
&6. \text{can't} \\
&7. \text{can't} \\
&8. \text{can} \\
&9. \text{mustn't} \\
&10. \text{must} \\
&11. \text{can} \\
&12. \text{can't} \\
&13. \text{mustn't} \\
&14. \text{Can} \\
&15. \text{couldn't} \\
&16. \text{mustn't} \\
&17. \text{mustn't} \\
&18. \text{can't} \\
&19. \text{couldn't} \\
&20. \text{can't} \\
&21. \text{mustn't} \\
&22. \text{can't}, \text{could} \\
&23. \text{must} \\
&24. \text{can't} \\
&25. \text{must} \\
\end{aligned}
}