A．低气压条件下沸腾的水
B．在烧杯里盛水加热
C．在高山上用敞口的锅烧水
D．用高压锅烧水
答案：D
The wallet was returned to him without anything _____.
A．missed
B．to be missed
C．missing
D．to miss
分级变速主传动系统的设计内容和步骤是什么？
