Dictionaries are important to us students. When we meet a new word, we can _____ in them.[ ]

A. look it up

B. look up it

C. look for it

D. look them up

在吸收塔中湿石灰石与氧化风机鼓送的（）和吸收塔中的（）发生反应达到了除掉（）中二氧化硫的目的