So        that even the students in the next classroom could hear his argument with somebody.

A．loudly he spoke

B．he spoke loudly

C．loudly did he speak

D．loudly spoke did he

内燃机按基本原理分类，有往复活塞式内燃机，旋转活塞式内燃机和（）等。

A、沼气机

B、涡轮式内燃机

C、汽油机

D、煤油机