They _________ on the program for almost one week before I joined them, and now we are still working on it as no good results have come out so far.
| A．have worked | B．had worked |
| C．have been working | D．had been working |
22. Miss Alice didn’t respond ___ my question in public , ___ made me angry with her .
| A．to , which | B．in , which | C．to , that | D．to , what |
21. --- Why don’t you like your job ?
--- It’s always being ___by my director .
| A．watched at | B．watched out | C．watched over | D．watched on |
20. The rest of his life was devoted ___ pollution ___more happily .
| A．to prevent , to live | B．to protecting , from living |
| C．to protect , from living | D．to preventing , to live |
19. --- Could you tell me how the sea sand comes about ?
--- Sea waves dash against the rock. In this way , the sea sand ___ .
| A．comes into use | B．comes into office | C．comes into effect | D．comes into being |
18. A new ___ bus service to Tianjin Airport started to operate two months ago .
| A．normal | B．usual | C．regular | D．common |