One theory, ________ suggested by Harvard University, is that humans began cooking their food, thereby releasing nutrients locked in the raw food and reducing the time needed to chew it.
| A．which | B．as |
| C．that | D．what |
Tell him ______ the light.
| A．to turn | B．not to turn on | C．to not turn | D．not to turn |
It took us more than two hours _______ the dinner.
| A．prepare | B．preparing | C．to prepare | D．to be prepared |
We felt the earth _______.
| A．move | B．moveing | C．to move | D．be moved |
The students were made ______ the text ten times.
| A．read | B．reading | C．to read | D．to be read |
The chair looks rather hard _______, but in fact it is very comfortable.
| A．to sit | B．to sit on | C．sitting | D．sit |