A: you must/mustn t put your hand up to ask a question b: what s the matter, officer ? you must/mustn t park your car here c: you must/mustn t do any sports d: you must/mustn tbuy a ticket before

exercise 10  

1. it has been snowing steadily the whole week and it is still snowing. 2. we have been climbing for six hours already, but we haven't reached the top of the mountain yet. 3. the pain has already gone but the child is still crying. 4. the workers have been working very hard these two weeks, they have been busy with the interior decoration of the house. 5. he has been solving the crossword puzzle for an hour and he says he is about to solve it as he is thinking over the last word. 6. he has been working at the language all the time and has made great progress. his pronunciation is rather good, only a slight accent has remained. 7. не has finished the first part of his book and now he is writing the second. he has been working at his book for two years. 8. dustin hoffman, who plays the hero, has given a fine performance. 9. why is your hair wet? have you been swimming? 10. doctors and scientists have shown recently the benefit of fish in the diet.  

exercise 14  

choose the right variant using the present perfect, the past simple or the past continuous tense.  

1. while i was waiting for him to call up, he was having a good time in the bar. 2. she (wrote) this exercise yesterday at 8 o'clock. 3. he (invited) me to the party yesterday. 4.i (have passed) my exam in history today. 5. he (read) a book two days ago. 6. they ( saw) this film last week. 7. she (was painting) the picture when i came. 8.i (was making) my report when you entered the hall. 9. they (were learning) the new words yesterday from three till seven. 10. it (has rained) this week. 11. she (was having) a bath at seven o'clock last night. 12. she (has washed) dishes already. 13. they (were having) supper when the telephone rang. 14. i (haven't met) you for ages. 15. last summer he (went) to the caucasus.