．Parents’ opinions on studying abroad differ greatly _____their children’s ____their aims．
| A．in; from | B．from; in | C．from; about | D．in; on |
When _____ different cultures, we often pay attention only to the differences without noticing the similarities.
| A．compared | B．being compared | C．comparing | D．having compared |
Hundreds of species are declared to _____ in the coming century.
| A．die away | B．die out | C．die down | D．die off |
It was playing computer games ____ cost the boy plenty of time ____ he ought to have spent doing his lessons.
| A．what; that | B．that; when | C．which; that | D．that; that |
We _____ live in a small flat but last year we bought a house.
| A．would | B．had to | C．used to | D．ought to |
All these gifts must be mailed immediately_________ in time for Christmas.
| A．in order to have received | B．in order to receive |
| C．so as to be received | D．so as to be receiving |