1. Max is not here. He is washing his car. He washes it every weekend. Действие происходит прямо сейчас, нужен Present continuous. То, что он моет машину каждую неделю - это повторяющееся действие, используем present simple.

2. He will not play the piano tomorrow. Tomorrow - маркер Future Simple.

3. We saw a very good film last Sunday. Last - маркер  Past simplte.

4. Does your mother cook every day? Every day - маркер Present simple.

5. We made a fire last summer. Last - маркер Past Simple.

6. I spent last summer at the seaside. Last - Past Simple.

7. Where did you spend last summer? Тоже самое, что и предыдущие.

8. Where will he spend next summer? Next - маркер Future Simple.

9. What is your mother doing now? Now - маркер Continuous. She is cooking dinner. Она сейчас готовит, поэтому Present Cont.

10. I did not play computer games yesterday. Yesterday - маркер Past simplte.

11. Last Sunday we went to the theatre. Last - маркер Past Simple.

12. I met my friend yesterday. Yesterday - маркер Past Simple.

13. I wrote a letter to my cousin yesterday. Тоже, что и в предыдущем.

14. Will you write a dictation tomorrow? Tomorrow - маркер Future Simple.

15. I am not writing a report now. Now - маркер Continuous.

16. Mother cooked a marvellous  dinner yesterday. Yesterday - маркер Past Simple.

17. Tomorrow Nick will not go to school. Tomorrow - маркер Future. I don`t think so.