1.Choose the right variant: You … cross the street when the light is red. A) should B) mustn’t C) need’t...

1. Choose the right variant: You mustn’t cross the street when the light is red. This is a rule for safety and you are not allowed to do it.
2. Choose the right variant: We must do our lessons every day. It is necessary for us to do our lessons regularly.
3. Choose the right variant: He can speak 2 foreign languages. He has the ability to speak in two different languages.
4. Choose the right variant: You must clean your teeth every day. It is important for your dental hygiene to clean your teeth daily.
5. Choose the right variant: Sorry, may I come in? Asking for permission to enter a room.
6. Choose the right variant: The weather is getting worse. It may rain. There is a possibility of rain based on the weather conditions.
7. Choose the right variant: Can your little daughter walk? - No, she can't. She is only eight months old. Asking about ability and receiving a negative response based on age.
8. Choose the correct article: I couldn’t see you yesterday. Expressing inability to see someone the day before.
9. Choose the right variant: Kate can speak English well. Kate has the ability to speak English fluently.
10. Choose the right variant: Will they be able to go to London next year? Questioning if someone will have the ability to travel to London in the future.
11. Choose the right variant: You should explain her how to get to Trafalgar Square. Giving advice on explaining directions to someone.
12. She couldn’t write her name until she was twelve. Describing the inability to write her name until a specific age.

1. B) mustn’t
2. C) must
3. B) can
4. E) clean
5. A) may
6. C) may
7. B) can
8. A) couldn’t
9. E) can
10. C) able
11. D) should
12. B) couldn’t

Let's analyze each question and determine the correct choice:

1. You … cross the street when the light is red.

   • B) mustn’t - "Mustn't" is used to indicate prohibition, which is suitable here because crossing the street when the light is red is prohibited.

2. We . do our lessons every day.

   • C) must - "Must" is used to express obligation or necessity, which fits the context of doing lessons daily.

3. He …speak 2 foreign languages.

   • B) can - "Can" is used to express ability, and it is appropriate here to indicate that he has the ability to speak two foreign languages.

4. You must … your teeth every day.

   • E) clean - The structure "must + base form of the verb" is correct here, so "clean" is the suitable choice.

5. Sorry, …I come in?

   • A) may - "May" is used to ask for permission politely.

6. The weather is getting worse. It . rain.

   • C) may - "May" is used to express possibility, which is appropriate for predicting weather conditions.

7. . your little daughter walk? - No, she can't. She is only eight months old.

   • B) can - "Can" is used to inquire about ability, which is suitable for asking whether the daughter can walk.

8. I’m sorry I … see you yesterday.

   • A) couldn’t - "Couldn't" is the past form of "cannot" and is used to express inability in the past.

9. Kate … speak English well.

   • E) can - "Can" indicates ability, and this choice conveys that Kate has the ability to speak English well.

10. Will they be … to go to London next year?

    • C) able - "Be able to" is used to express capability or possibility in the future.

11. You … explain her how to get to Trafalgar Square.

    • D) should - "Should" is used to give advice or a recommendation, which fits the context of explaining directions.

12. She … write her name until she was twelve.

    • B) couldn’t - "Couldn't" indicates inability in the past, which matches the context of not being able to write her name until age twelve.

These answers reflect the proper usage of modal verbs and grammatical constructions in English to convey meaning accurately.