If you want to catch the first bus you’d better ________ for the bus station immediately.
| A．set up | B．set about | C．set down | D．set off |
________ H7N9 is a deadly virus, it is still safe to eat thoroughlycooked chicken.
| A．Until | B．While |
| C．If | D．Since |
I will accept Guy coming with us, ________ he pays for his own meals.
| A．only if | B．so that |
| C．ever since | D．even though |
Scientists are warning that ________ emissions of carbon (碳排放) are cut, we could be heading for an environmental disaster.
| A．before | B．as |
| C．unless | D．in case |
——Did you inform Helen of the plan put forward at the meeting?
—Of course. ________ I saw her.
| A．So long as | B．If only |
| C．The moment | D．Any time |
Please call my secretary to arrange a meeting this afternoon, or ________ it is convenient to you.
| A．whenever | B．however |
| C．whichever | D．wherever |