Visitors not to touch the exhibits.
| A．will request | B．request |
| C．are requested | D．are requesting |
Miss Green contributed fifty dollars, but she wished she could contribute _____.
| A．one other fifty dollars | B．the same amount also |
| C．more fifty dollars | D．another fifty |
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 |