4. Fill in the negative form of the verb to be: 1. They students. 2. Sam in the gym. 3. Kate twelve years old. 4. We in London. 5. The dog under the table. 6. I in the museum. 7. You twelve years old. 8. She a dancer 9. We friends.

1. They are not students.
To form the negative form of the verb "to be," we add "not" after the verb. In this case, "are" is the verb we need to negate, so we place "not" after it to give us "are not."

2. Sam is not in the gym.
Again, we add "not" after the verb "is" to form the negative form. So, "is not" is the negative form of "is."

3. Kate is not twelve years old.
Similarly, we add "not" after the verb "is" to negate it. Therefore, "is not" is the negative form of "is."

4. We are not in London.
Once more, we insert "not" after the verb "are" to create the negative form. Thus, "are not" is the negative form of "are."

5. The dog is not under the table.
We add "not" after the verb "is" to make it negative. Hence, "is not" is the negative form of "is."

6. I am not in the museum.
To negate the verb "am," we add "not" after it. Consequently, "am not" is the negative form of "am."

7. You are not twelve years old.
As before, we insert "not" after the verb "are" to form the negative form. Thus, "are not" is the negative form of "are."

8. She is not a dancer.
To negate the verb "is," we add "not" after it. Thus, "is not" is the negative form of "is."

9. We are not friends.
We place "not" after the verb "are" to create the negative form. Therefore, "are not" is the negative form of "are."

By adding "not" after the verb "to be," we create the negative form of the verb. This indicates that something is not true or not the case. It is important to remember the correct form of the verb "to be" (am, is, are) and place "not" after it to construct the negative form accurately.