展现的

It also gives themechanical energy of the particle france and the expression of the conservation law of mechanical energy ,and discusses the statement on the consenvation law of mechanical energy in same books.

给出了守恒和守恒定律的定义，并给出了质点组的机械能及机械能守恒定律的表述，还对一些文献关于机械能守恒定律的论述进行了讨

We must not depreciate the work that she has done.

我们不要轻视她所做的工作。