invaluable service

难以估量其重要性。
常用释义
非常宝贵的服务：指提供的服务非常有价值，难以估量其重要性。

例句

But it is such an invaluable service that both sides are glad to pay him liberally for it.

但正是这样一种看似毫无价值的服务使得两边的人都乐意好好酬谢他。

不过，怀疑论者发挥着宝贵作用。

If the parent is a chief executive with a big ego, this is an invaluable service, as no one else would dare perform it.

如果父母是自视甚高的CEO，这可算是无价的忠言，因为别人谁也不敢这么说。

勒格兰做出了一项宝贵的贡献：他为缺乏认同的人口自由流动原因，提供了有力的论据。