Choose the best answer A, B, C or D to complete the sentences 17. You__________ run so fast at first. It's better to start by jogging slowly. A. should not B. need not C. cannot D. mustnt 18. Healthy food and exercise help us __________ fit. A. keep B. not keep C. feel D. feeling 27. We ______ very busy last week. A. was B. am C. were D. will be 30.Yesterday we___ to an interesting lecture about coloured vegetables in our cooking classes. A. read B. study C. listened D. studied 31. -" Would you like me to turn off your computer? " ......... I'll do it myself" A. No, thanks B. Yes, please C. Don't do it D. Of course