Nuclear ______ be really dangerous at times even though it’s a nice energy in general．
| A．shall | B．should | C．can | D．Must |
We have every reason to believe that our business has shown a(n) ____ to improve.
| A．direction | B．tendency | C．aspect | D．effect |
A good husband must know how to ____ his ideas to his wife.
| A．contribute | B．consult | C．comfort | D．convey |
____ most efficient way to understand thousands of new words is to gain ____ good knowledge of basic word information.
| A．A; a. | B．The; / | C．A; / | D．The; the |
–– I’m sorry to have broken your pen. I wasn’t on purpose.
––_______. I’ve got another one.
| A．Go ahead. | B．Forget it. | C．Come on. | D．Take your time. |
All the photographs in this book, _______ stated otherwise, date from the 1970s.
| A．until | B．once | C．if | D．unless |