白芷内酯属于( ) A．简单香豆素 B．线型呋喃香豆素 C．角型呋喃香豆

试举例说出两种发酵产品，并说明它们和你生活有什么关系．

Those successful deaf dancers think that dancing is an activity ______ sight matters more than hearing. [ ]

A. when

B. whose

C. which

D. where

根据句意和汉语注释，在空格内写出单词的正确形式

小题1:There is more  ______ (污染) in our city now than before.

小题2:The Summer Palace is a beautiful and ________ (安静的) place.

小题3:Now many new teachers go to teach children in the _______ (西北方) of China.

小题4:It is polite of us to give our seats to       （患病的）people on the bus.

小题5:When we go on a school trip, we’d better wear _______ (舒适的)clothes.

我国大型及以上企业第四季度景气指数与小型企业第二季度景气指数的比例为( )。

A．100:68.7

B．100:76.8

C．100:74.7

D．100:76.5

缸胀和胀差的监视的目的是什么？