They have to explain ______ us the reason _____ their doing so.
| A．/; of | B．with; about | C．/; for | D．to; for |
By the middle of the 21st century, the vast majority of the world’s population _____ in cities rather than in the country.
| A．are living | B．will be living | C．have lived | D．will have lived |
--- I need to advertise for a roommate for next term.
--- _____? Mary is interested.
| A．Why bother | B．Why not | C．So what | D．What for |
A major earthquake _____ 8.0 on the Richter scale strongly _____ Wenchuan County in Sichuan Province at 2:28 p.m. on May 12, 2008.
| A．measured; shaken | B．measured; shaking |
| C．measuring; shook | D．measuring; shaking |
It was in the small house _____ was built with stones by his father _____ he spent his childhood.
| A．which, that | B．that, which | C．which, which | D．that, where |
--- May I go and play with Dick this afternoon, Mum?
--- No, you can’t go out _____ your work is being done.
| A．before | B．until | C．as | D．the moment |