As time went by , the theory he had stuck ______ correct .
| A．to prove | B．to proving | C．to proved | D．to be proved |
The fact that smoking is harmful to health is____most smokers are quite aware of．
| A．what | B．which | C．where | D．that |
An example of them is fraud, a crime _______ money is stolen by cheating others.
| A．which | B．that | C．what | D．where |
Dr. Frank failed many times but he finally _____ to find a successful way to solve the problem.
| A．broke off | B．broke up | C．broke down | D．broke through |
---Where have you been?
---I got caught in traffic, otherwise I _______ here earlier.
| A．would be | B．have been | C．had been | D．would have been |
—May I ask a question after class，sir?
—____，but not during my lunch break．
| A．Take it easy | B．No way | C．Certainly | D．Go ahead |