So mysteriously ______ missing that many puzzles wait to be solved.
| A．did Flight MH370 go |
| B．Flight MH370 went |
| C．does Flight MH370 go |
| D．had Flight MH370 gone |
We human beings should be very careful with what we do with nature, _____power is beyond our understanding.
| A．that | B．which |
| C．whose | D．where |
（）I found the lecture hard to follow because it ____ when I arrived.
| A．started | B．was starting |
| C．would start | D．had started |
I haven’t finished my report, but I promise I ______ it by the end of the week.
| A．will finish | B．have finished |
| C．will be finishing | D．will have finished |
It's a custom in China to have some tea or other drinks before the meal ________.
| A．serves | B．served |
| C．was served | D．is served |
—What’s all that noise about outside?
—Oh, I forgot to tell you. The road to the railway station ______.
| A．will be widened | B．is to be widened |
| C．has been widened | D．is being widened |