_______, ice can be changed into water and water can be changed into steam.
| A．Heat | B．Heating |
| C．To heat | D．Heated |
____ of their bad habits, the boys switched from being dependent on their parents to ____ for others.
| A．Having rid; sacrificing | B．Rid; sacrificing |
| C．Having been rid; sacrifice | D．To rid; sacrifice |
These old buildings possibly ____ the Ming Dynasty.
| A．date back to | B．dated back to | C．dated from | D．date in |
I can’t bear ____, so I hope you can come on time.
| A．to keep waiting | B．to keep to wait |
| C．being kept waiting | D．being kept to wait |
I wonder such a gentleman as he should ____ an error, though it is a simple and small one.
| A．admit | B．tolerate | C．commit | D．ignore |
A study shows that students living in non-smoking dormitories are less likely to ____ the habit of smoking.
| A．make up | B．turn up | C．draw up | D．pick up |