11. The chemistry teacher required the students _______ more attention _______ the lab clean.

A. to pay, to keep     B. to paying, to keeping  C. to pay, to keeping      D. paying, keeping

We have produced 15% more cotton this year____ we did last year.

A. as                B. than           C. like            D. white

Write clearly ____ your teacher can understand .you correctly.

A. since            B. for           C. because                      D. so that

Some people say that we live _____ the age of computers.

A. in 　　                 B. at 　　                      C. with 　　          D. for

I made the coat ____ my own hands. It was made ____ hand, not with a machine.

A. in; in             B.in; with               C. with; by               D. with; with

Do you often hear____ your brother?  

A. of                       B. from               C. out of       D. about

This is a common mistake ____ students.                  

A. between        B.over             C. among         D. about

ou can't wear a blue jacket _____ that shirt — it'll look terrible.

 A. on               B. above          C. up         D. over

He lay ___ the grass was the thickest.   A. where     B. when    C. that       D. after

___ I know he will stay here for half a year.

A. as soon as                 B. as long as            C. so far as            D. as well as