The scientists have already written their 3article.
1. Pete’s hamster has just eaten his food.
2. The boys found yesterday an old cage in their garden.
3. He hasn't discussed the problem yet
4. Charles has jusr finished his dictation.
5. We went to the theatre last Sunday.
6. Kate has been to the library three times this week.
7. Don’t buy pizza! I have already cooked an apple pie.
8. Let’s have breakfast! Mike has just set the table.
10.My mother is angry. My elder sister hasn't taken out rubbish.
9. I know who your boss is. I have worked for him.
10. Look! Somebody has already broken the tree.
11. Mary has gone to Moskow, but she’ll be back next Monday at the latest.
12. Andy is in hospital now. He has had a bad crash.
13. Jane is crying. She has hurt her knee.