When ________how a statue from distant Greece, in China, researchers explained that it was no doubt a result of Alexander the Great’s influence．
| A．they were asked; should appear; |
| B．being asked; can have appeared; |
| C．asked; must have appeared; |
| D．asked; could have appeared; |
－How did you find those days．
－The days________ we spent together on the farm are not easy________．
| A．that；to forget | B．when；to be forgotten |
| C．when；to forget | D．that；to be forgotten |
George once told me that he would visit our house，but，for various reasons，he ________so far．
| A．didn't | B．hasn't | C．hadn't | D．wouldn't |
Premier Li Keqiang delivered a speech at the conference, _________ university graduates to start their own business.
| A．encouraging | B．to encourage |
| C．having encouraged | D．encouraged |
—What do you think of the Huawei P7?
—Terrific, I would buy one if I ______ an iPhone 6 Plus last year.
| A．didn’t buy | B．don’t buy |
| C．hadn’t bought | D．haven’t bought |
______ worries me that my daughter plays with her cellphone for a long time every day.
| A．It | B．What | C．This | D．That |