17. B. Put off: trì hoãn
18. D. Remains in effect: còn tác dụng
19. B. Length
20. A. Railway
21. A. Seriously
22. D. Renamed
23. C. Passengers
24. A. Teachers from learning centers will give them help through live conferencing
25. D. Learn social skills
Xin hay nhất ạ :)
@rene@