Перефразируйте следующие пред¬ложения, употребляя модальный глагол must.
1. You have been absent very long. I am sun you feel hungry. 2. Where are the children? -They are at the river with Nick. I am sure they an having a very good time. 3. He has probably worke’ very hard to finish his book. 4. She is a very expe rienced doctor. I am sure she has been working at this hospital for at least fifteen years. 5. Look! Helen’s windows are open. I feel sure she is at home. 6. The Smiths have always been great foot¬ball fans. I am sure they are at the stadium watch¬ing the football match. 7. Probably they have changed the school programme. My granddaugh ter knows a great deal more than I did when I was her age. 8. It is probably a very difficult rule. 9. I am sure it is pleasant to spend summer in such a picturesque place. 10. You have probably read books of this author before. 11. I feel sure they are pre¬paring a surprise for us. 12. These old legends were probably composed about a thousand years ago. 13. It is probably nine o’clock now. 14. He is very old. I think he is nearly eighty. 15. It is prob-ably time to go now.