When we practice _____ English, we often end up _____ in Chinese. [ ]

A. speak, to speak

B. spoken, speak

C. speaking, speaking

D. to speak, speak

以小组（）来划分，可以将小组分为组成小组和自然小组。

A.组员参与和动机

B.组员间的联系

C.小组的结构

D.组员之间的界限

E.形成方式