We do not permit _________ in the office.
| A．to smoke | B．to smoking | C．for smoking | D．smoking |
with College Entrance Exam slogans, the walls of the classroom look better．
| A．Having decorated | B．Being decorated | C．To be decorated | D．Decorated |
You should study the details of the policy before you sign it.
| A．in return | B．in advance | C．at ease | D．on purpose |
If we keep wasting so much energy, ________are that our oil wells will dry up and the environment will be destroyed.
| A．problems | B．difficulties | C．questions | D．chances |
You may imagine what great difficulty I had ________ complicated ideas in simple English.
| A．expressing | B．to express | C．expressed | D．express |
The incomes of skilled workers went up. ________，unskilled workers saw their earnings fall.
| A．Moreover | B．Therefore | C．Meanwhile | D．Otherwise |