EXERCISE I: Put the verbs in brackets in correct tenses. 1/ If I (have) ________ a typewriter, I could type it myself. 2/ If I had known that you were in hospital, I (visit) ________ you. 3/ You could make much progress if you (attend) ________ class regularly. 4/ If I (know) ________ his telephone number, I would give it to you. 5/ If you (arrive) ________ ten minutes earlier, you would have got a seat. 6/ If he (study) ________ harder, he can pass an exam. 7/ She may be late if she (not hurry) ________. 8/ Tell him to ring me if you (see) ________ him. 9/ If you (speak) ________ more slowly,he might have understood you. 10/ What (you do) ________ if you got fat? Exercise III: complete the sentences 1. If we meet at 9:30, we (have) _________________plenty of time. 2. If you (find) _______ a skeleton in the cellar, don't mention it to anyone. 3. The zookeeper would have punished her with a fine if she ( feed) _________________ the animals.. 4. If you pass your examination, we (have) _________________a celebration. 5. Lisa would find the milk if she (look) _________________ for it in the fridge. 6. What (happen) _________________if I press this button? 7. The door will be unlocked if you (press)___________ the green button. 8. I should have voted for her if I (have) _________________ a vote then. 9. If you go to Paris, where you (stay) _________________? 10. If you (swim) _________________ in this lake, you'll shiver from cold. 11. If someone offered to buy you one of those rings, which you (choose) _________________? 12. The flight may be cancelled if the fog (get) _________________thick. 13. If the milkman (come) _________________, tell him to leave two pints. 14. I (call) _________________ the office if I were you. 15. Someone (sit) ________________on your glasses if you leave them there. 16. You would hear my explanation if you (not talk) ____________so much. 17. What I (do) _________________if I hear the burglar alarm? 18. If you (read) _________________the instructions carefully, you wouldn't have answered the wrong question. 19. If Mel (ask) _________________ her teacher, he'd have answered her questions. 20. I would repair the roof myself if I (have) ____________a long ladder. trả lời giúp với.