——These grapes look really beautiful．
——They ______！See the price，$3．99 a pound．Very expensive，aren’t they！
| A．would | B．could | C．might | D．should |
A huge amount of oil was spilt on the East Sea，the causes of ________ are still under investigation．
| A．it | B．that | C．which | D．whom |
——Has James finished his report on his Enquiry Learning yet？
——I’m not sure．She _________ on it last week．
| A．was working | B．has worked |
| C．worked | D．had worked |
None of the underwater workers has been harmed by the great fish. ______，most fish were so friendly that they played with the instruments.
| A．Instead | B．Even though |
| C．However | D．Though |
Alibaba has become China’s largest online commercial company，______ a profit of 1.47 billion yuan in 2010.
| A．earns | B．earning |
| C．earned | D．to have earned |