消防员灭火防护服的（）部分，是用于提供隔热保护的防护服部分。
A.外层
B.防水透气层
C.隔热层
D.舒适层
参考答案：C
The old woman became aware of when she left the market. [ ]
A．cheating
B．cheated
C．being cheated
D．to be cheated
回转减速机的特点有哪些？
