(2013·哈尔滨四校高三统一检测)My mother went to the private school in person ________ that I would be safe there.

A．confirming

B．having confirmed

C．to confirm

D．confirmed

分子筛纯化器的结构分为（）等几类。

A、单层筒体内绝热；

B、单层筒体外绝热；

C、双层筒体内绝热；

D、双层筒体外绝热。