--- Could you tell me __________?
--- Certainly. In half an hour.
| A．when will the train to Beijing leave |
| B．when the train to Beijing would leave |
| C．when the train to Beijing left |
| D．when the train to Beijing will leave |
For the safety, everyone _________ obey the traffic rules when he is driving or walking.
| A．need | B．must | C．may | D．could |
This summer vocation I am going to do a lot of _________ to prepare for the senior high school.
| A．job | B．work | C．invention | D．service |
--Did you see Mary and her sister this morning?
-- Yes, I saw _________ girls playing in the playground.
| A．either | B．neither | C．any | D．both |
Although advertisements enable _________ to make decisions quickly, they sometimes cause lots of trouble.
| A．we | B．our | C．us | D．ours |
Over 20 countries joined to search _________ Flight MH370 in the southern Indian Ocean.
| A．of | B．for | C．in | D．from |