Ответ:

1 упражнение

snows

is snowing

cooks

leaves

is leaving

watch

are sitting

are watching

does

is doing

rains

is raining

has

has

Упражнение 1

1. Snows

2. Is snowing

3. Cooks

4. Is cooking

5. Leaves

6. Is leaving

7. Watch

8. Are sitting

9. Does

10. Is doing

11. Rains

12. Is raining

13. Has

14. Is having

Упражнение 2 (в скобочках указываю слова по которым определяют время в предложении)

1. Goes (often)

2. Are watching (at the moment)

3. Writes (every week)

4. Drives (usually)

5. Is sitting (now)

6. Is ringing (listen)

7. Studies (every year)

8. Spend (always)

9. Go (usually)

10. Is riding (look)

Упражнение 3

1. Aren't

2. Don't

3. Isn't

4. Am not

5. Doesn't

6. Isn't

7. Doesn't

8. Am not

9. Don't

10. Doesn't

Упражнение 4

1. Do

2. Are

3. Does