Scientists think they have _____ in their attempt to find the causes of some major dieases.
| A．broken through | B．worked out |
| C．fallen out | D．got round |
—Who did it?
—.you ask?It was Joe,of course.
| A．May | B．Must | C．Should | D．Need |
Her father is a famous writer,always makes her very proud.
| A．that | B．which | C．who | D．what |
The people you find most diffcultcan also be your most valuable teachers.
| A．dealing with | B．to be dealt with | C．to deal with | D．being dealt with |
I don’t like talking ontelephone；I prefer writingletter.
| A．the；a | B．不填；a | C．不填；the | D．the；不填 |
—Would you ever let him work here again?
—!Not after the way he treated me.
| A．Of course | B．Come on | C．No way | D．Not at all |