9. We A. must 10..... A. How 11. He A. to walk 12. A. How 14. Going by. A. train 13. My sister used to go to work A. to B. in 16. He A. sails to school every morning. B. go by walk 18. How about A. go obey traffic rules for safety. B. mustn't does Tom go to school? - By bus. B. What 15. You should notice. on the right way. A. bus 19. Use A. pavement is fast, but expensive. B. plane C. walks D. go walk did you stay last summer vacation? - In my uncle's farm. B. What C. When D. Where 17. My grandfather often. A. to walk B. motorbike a boat over sea by himself. B. ride B. drive TRÊN INUYỆN B. going C. can C. When bike. when crossing the street. B. zebra C. on D. can't C. bike when you are on the road. They help you go D. Where C. drive D. by D. motorbike C. road signs D. trees D. fly for exercise in the morning. C. get off D. cycles C. zebra crossing to the Temper of Literature by bus tomorrow? C. to go D. goes D. crossing