The manager of the company told us that very little _________ was made of the waste material in the past.
| A．cost | B．value | C．matter | D．use |
They are going to find a new approach ______these complex problems.
| A．to solving | B．to solve | C．in solving | D．solves |
I'm afraid that I can't make myself _______ because of my poor English.
| A．understand | B．understanding | C．to understand | D．understood |
That dog ought to be destroyed ______it attacks any more children.
| A．until | B．since | C．after | D．before |
The library needs __________, but it’ll have to wait until Sunday.
| A．cleaning | B．be cleaned | C．clean | D．being cleaned |
The 1930s __________ the suffering of the Chinese from war.
| A．wrote | B．witnessed | C．proved | D．supplied |