She definitely had an ulterior motive in offering to help.

她提出帮忙, 肯定有不可告人的机。

When this method is applied to the spiral bevel gears of an airplane engine, the results show that it is more reasonable than TCA and the precontrol method.

提出了一种在初始设计阶段可保证弧齿锥齿轮具有预期加载接触性能的设计方法，并于某航空发机中央传弧齿锥齿轮的齿面综合。