31. Tom and his father_______America last week, and arrived there this Tuesday morning.
| A．set for | B．set off | C．set off for | D．set off to |
Scientists have achievedr a major_______ in the search for a cure for cancer, _____ is good news for those who suffer from cancer
| A．breakthrough; what | B．breakdown; which |
| C．breakup; that | D．breakthrough; which |
-----Thank you for the great favor you _____me in face of difficulty.
-----It is no ______at all. Helping others also benefit me .
| A．make; trouble | B．do; bother | C．give; wonder | D．do; use |
My early_______ at learning playing the piano was a failure although I took a fancy to it.
| A．attempt | B．effort | C．assumption | D．intention |
It was on my way back home ______ my teacher made the promise______I can do nicely next exam I will buy me a set of LuXun’s Complete Works.
| A．when; that | B．when; that if | C．that; why | D．that; that if |
He's obviously quite embarrassed about it because he _____ me to tell anyone.
| A．prevented | B．kept | C．permitted | D．forbade |