Present perfect

2. Children/to swim/for half an hour.

3. He/to speak/on the phone/for an hour now.

4. You/to wait/for a bus/for ten minutes only.

5. It/to snow/since last night.

1. Don't walk in here. I …(just/clean) the floor.

2. Jane is hungry. She …(not /eat) anything for six hours.

3. She is tired. She …(study) for four hours.

4. I don't want to see that film again. I …(see) it twice already.

5. He …(walk) all the morning.

Нет ни одного правильного предложения. Почти все предложения - III тип условных предложений
В главном предложении would have и смысловой глагол в III форме, а в придаточном had и III форма смыслового глагола 

2. He will work harder in French lessons if he has a French penfriend.
3. If he had been ill on the day of the exam could he have taken it at another time?
4. If I had enjoyed studying, I would have gone to university.
5. If she had left home earlier, would she have got to the interview on time?
6. My parents would not have been angry if I had phoned and told them where i was.
7. If I had not slept late this morning, I wouldn't have missed breakfast.
8. Could she have got the job if she had not known the boss?
9. I would not have known anything about Picasso if we had not learned about him at school. 
10. A lot of people wouldn't have been successful if they had been discouraged by their failures.

Both of them were surprised when they heard this, 2 Both of us were doing our best.  3 Both of them looked puzzled. 4 This is a good article. The information is it is both interesting and important for the book which I am working on. I am grateful to both of you that you got it for me. 

Do you need a receipt? - Yes, I'd better take it. 2 I'm afraid I can't give this magazine/journal to you today, I need it myself. 3 Do you still need a phone? - No, thank you, you may use it. 4 You needn't come here. You can either call us or send us a note with your younger brother. 5 Shall I translate this sentence immediately. - No you needn't. You may think a little bit. 

Don't worry about our son/ about this/ about his health. 
Don't bother call him/ remind him about this/ fill in the blank
Does this noise/ radio/ TV trouble us?