It isn’t clear_____ is to blame.We need to find a solution to the problem first.
| A．who is it that | B．who it is that | C．it is who that | D．that who it is |
It was not until 1911, _______ the first vitamin was identified, _______ people realized the importance of it．
| A．when; which | B．when; that | C．that; which | D．that; that |
The moment I completed the 800-meter race in the school sports meet, my legs _______．
| A．gave out | B．gave away | C．gave in | D．gave up |
We’ve just heard a warning on the radio _______ a typhoon may be on its way．
| A．what | B．when | C．which | D．that |
Traditional Chinese medicine is thousands of years old and has developed _______ time．
| A．over | B．in | C．on | D．of |
_______ with the Japanese government, some Chinese people decided not to buy products from Japan any more．
| A．Not satisfying | B．Not having satisfied |
| C．Not satisfied | D．Not to satisfy |