You _____ pay too much attention to your reading skill, as it is so important.
| A．cannot | B．should | C．must | D．needn’t |
The professor devoted all his life __________ the treatment of AIDS.
| A．to research |
| B．in researching |
| C．to researching |
| D．at researching |
He was __________ down for several days after he heard the bad news.
| A．broken |
| B．cast |
| C．cut |
| D．discouraged |
They all looked down upon him. He was __________ a singer.
| A．not more than |
| B．less than |
| C．no more than |
| D．more than |
In the experiment we kept a watchful eye __________ the development and recorded every detail.
| A．with |
| B．on |
| C．for |
| D．to |
My interest in collecting stamps __________ my childhood.
| A．dates from |
| B．dated from |
| C．dated back to |
| D．went back to |