One end of a cylinder for a medium or high-speed diesel engine is sealed by the piston and

A.at one’s wits end

B.in his wits end

C.at his wits’ end

D.out of his wits end

A.penicillin

B.insulin

C.Prontosil

D.vaccines

Where did one of the runners fall down？

A．50 meters from the end.

B．15 meters from the end,

C．10 meters from the end,

D．5 meters from the end.

A．Do the assignments towards the end of the semester.

B．Quit the history course and choose another one instead.

C．Drop one course and do it next semester.

D．Take courses with a lighter workload.

"...one would have expected the episode to end there" in the fourth paragraph means that

A．things might not go from bad to worse.

B．the doctor tried to cure fits.

C．more people suffered from fits.

D．the situation was further aggravated.

A、The Great Wall of China is over 8,800 kilometers from one end to the other.

B、The Great Wall of China is over 8,800 kilometers from one end to the other.

C、/

D、/

At the end of one month, the boys (looked forward to) their mother's (return) most earnestly, (as) they were really (tired with) their father's boiled eggs.

A．looked forward to

B．return

C．as

D．tired with

We can infer from the last paragraph that

A.the end of one business expansion will certainly happen

B.the business can expand endlessly

C.economic expansion is fast

D.economic rise to the peak is slow