It’s difficult to ___ these old books for some of them ______ none of the classification.
| A．look for; are belonging to | B．put up; belong |
| C．sort out; belong to | D．pick up; are belonged to |
—But I don't know how to play the piano.
— __________.
| A．So do I | B．Neither will I |
| C．Me too | D．Neither do I |
He tried his best to solve the problem, __________ difficult it was.
| A．however | B．no matter |
| C．whatever | D．although |
__________ private cars are bringing us convenience, they may also cause more traffic accidents and pollution.
| A．While | B．As | C．If | D．Since |
To their __________, young people in China, ignorant about Chinese traditional holidays, are crazy about Christmas or Valentine's Day.
| A．enjoyment | B．satisfaction |
| C．astonishment | D．relief |
__________ encouraged me most at that time was the comments of the teachers and my friends.
| A．Who | B．What | C．Which | D．That |