We could see nothing because the lights suddenly _______.
A. went on B. went over c, went down D. went out
I’ll go to the library as soon as I finish what I .
| A．was doing | B．am doing | C．have done | D．had been doing |
Sarah looked at finished painting with satisfaction.
| A．不填；a | B．a; the | C．the;不填 | D．the;a |
Tom asked the candy makers if they could make the chocolate easier into small pieces.
| A．break | B．breaking | C．broken | D．to break |
In our class there are 46 students,half wear glasses.
| A．in whom | B．in them | C．of whom | D．of them |
All the photographs in this book,stated otherwise, date from the 1950s.
| A．unless | B．until | C．once | D．if |