Fill in the blanks with the most appropriate modal verbs: must, have to, can, should, shouldn't.

Here are the answers:

1. My mother told me to come home by nine o'clock. I must go now.

   • The correct option is A) must. "Must" indicates a strong obligation or necessity.

2. On Saturday and Sunday mornings, we don't have to get up early.

   • The correct option is B) don't have to. This indicates a lack of obligation.

3. We can play football on the school field after school. We won't miss it.

   • The correct option is B) can. "Can" indicates possibility or ability.

4. You shouldn't eat a lot of sweets.

   • The correct option is B) shouldn't. "Shouldn't" is used to give advice or recommend against something.

5. You should drink plenty of clean water.

   • The correct option is B) should. "Should" is used to give advice or make a recommendation.