I should not have laughed if I ________ you were serious.
| A．thought | B．would think |
| C．had thought | D．have thought |
In Hangzhou, Mr. Black was so struck ______ the beauty of nature that he stayed
________ another night.
| A．at ; on | B．with ; at | C．for ; in | D．by ; for |
.It is morning _____ we have four classes, not afternoon.
| A．when | B．which | C．that | D．why |
Mother told Jim to watch the milk until it boiled and then _________ off the gas.
| A．turn | B．turning | C．turned | D．having turned |
The idea puzzled me so much that I stopped for a few seconds to try to _______.
| A．make it out | B．make it off | C．make it up | D．make it over |
One of the walls of the reading--room should be painted yellow, and ______.
A. the other is white B. the others white
C. the other white D, another is white