白术的主要归经是（）
A.肺胃经
B.肺心经
C.脾胃经
D.肝肾经
E.心肝经
参考答案：C
--- What did the professor tell you to do?
--- I had to write a ________ report.
A．three-thousand words
B．three thousands word
C．three-thousand-word
D．three-thousand-words
制取一氯乙烷最好的方法是（ ）
A．乙烷和氯气在光照下取代反应
B．乙烯和氯气加成反应
C．乙烯和氯化氢加成反应
D．乙烯和氢气、氯气反应
--- I had to write a ________ report.