问题描述：
[单选]
The trouble-free life of an engine indicates（）．
A．the period of time during which no trouble occurs to the engine
B．no trouble will occur to the engine all its life
C．trouble may occur freely to the engine
D．no matter what you do to the engine, no trouble will occur during this period
参考答案：查看无
答案解析：无
☆收藏
答案解析：无
☆收藏
上一篇：When we say that two objects have relative motion， we mean（）．
下一篇：General， the best way for replacement of lamp is（）．
- 我要回答: 网友(216.73.216.96)
- 热门题目: 1.保证和提高船舶动力装置的可靠 2.当船舶机动航行时（）。Ⅰ.只 3.平均寿命E（t）是个箅术平均