1. Perhaps some light exercise could / must relieve the pain. 2. He fell asleep at his desk! He might / must have been exhausted. 3. Ann isn't here, She must / can't have forgotten. 4. You don't have to / shouldn't exercise when you don't feel well. 5. She's walking to school. She might / can't have missed the bus. 6. He can't / could have gone home. He's left his bag on the chair. 7. We mustn't / don't have to learn Chinese. 8. Tania's in Spain. You must / could have seen someone else.
2) To be honest, I read this book in translation.
3) He knows englis well enough, to translate this article.
4) First, that need to do, - is to type new words from text.
5) It is useless to conflict with you; you are very stubborn.
6) It is never late to recognize your mistake.
7) She went to Far East and haven't comebacked in her's hometown.
8) To put it mildly, he didn't tell all truth to you.
9) I feel myself very bad, to go with you out of town.
10) In short, their fault still hasn't proved .