【单选题】How many categories does the writer classify into?
A.
There are two categories.
B.
There are three categories.
【简答题】The two categories of crystalimperfections are A) ______ and B) ______
【单选题】零件加工表面具有的较小间距的峰谷所组成的微观几何形状特性,称为 。
【多选题】What categories are currently not available for sale?
【多选题】Which categories of words are deixis?
C.
time and place adverbs
D.
some grammatical categories such as tenses