—How many students are there in your school?

—About _____. And one third of them _____ girls.

A. two thousand; is                  

B. two thousands; is

C. two thousand; are                  

D. two thousands; are

不要给不准备手术的甲亢病人服用碘剂，主要因为（）

A.一旦停服，甲亢症状重现，甚至更严重

B.碘剂对减轻甲亢症状的疗效不显著

C.碘剂不能降低甲亢病人的基础代谢率

D.碘剂效果不如普萘洛尔

E.病人经常不能耐受碘剂治疗