The police were seeking more information to find out _____ the rich merchant.
| A．who was it that killed | B．who it was that killed |
| C．it was who killed | D．who was it killed |
Each member country WTO must ___________ its laws and regulations and compete on the principle of fairness and cooperation.
| A．submit to | B．cater to | C．correspond to | D． relate to |
Mary ______ all the housework, she dropped herself into the sofa, sighing with relief.
| A．finished | B．had finished | C．having finished | D．finishing |
Scientists say human activity contributes to climate change, but they do not agree on the rate_______ climate change may be developing.
| A．with which | B．with that | C．at which | D．at that |
Everybody has ______ responsibility to save water, if future generations are to enjoy _____similar standard of living to the one we enjoy now.
| A．the; / | B．a; a | C．/; the | D．a; the |
______ the new life in Qingdao, the old man lived happily with his son after leaving his home in the countryside.
| A．Accustomed to | B．Accustoming to |
| C．Having accustomed to | D．having used to |