Mr. Smith went to a bookstore, where a lot of books were .
| A．produced | B．invented | C．housed | D．disappeared |
For _______information about present national boundaries, we’d better refer to an up-to-date map.
| A．practical | B．frequent | C．reliable | D．beneficial |
When you are in trouble, you may _______ your teacher and classmates for help.
| A．turn away | B． turn around | C．turn back | D．turn to |
The number of the people who can afford to buy their own house ______ more than 60%,but a number of houses _______.
| A．are; hasn’t been built | B．are; has built | C．is; haven’t been built | D．is; have built |
I didn’t get a pay rise, but that wasn’t the right reason _______I left.
| A．how | B．at which | C．when | D．for which |
He started to study ecology and decided to _______his whole life to the science.
| A．ignore | B．devote | C．prefer | D．lead |