Question

Radium salts，which have been found to ______ in bones，give rise to bone cancer.

1. A.
   pile up　
2. B.
   build up
3. C.
   keep up　
4. D.
   pull up

Answer 1

B
考查短语辨析。build up(="accumulate)" 积累。pile up 堆积。keep up 保持，维持。 pull up 停车。根据句意选B。