吊架零部件加工制作时，碳素钢部件在环境温度低于-20℃，合金钢在环境温度低于（）℃时不宜采用机械冲剪。
A、-10
B、-5
C、O
参考答案：C
The 16-year-old _____ often shares her _____ and sadness with her best friend.
A．teenager; joy
B．teenager; joys
C．baby; joy
D．man; joys
设计（或实用）通行能力
