定期维修可保持发动机的顺畅运转。

Regular servicing guarantees the smooth operation of the engine.

《牛津词典》

没有润滑油发动机就不能运转。

Engines won't run without lubricants.

《牛津词典》

发动机似乎运转正常。

The engine seems to be performing well.

《牛津词典》

It's just like you could say some of the principles of mechanics are very obvious, but to make an engine that operates in terms of those principles is not obvious.

这就像你能说,很多机械原理都显而易见，但是要根据这些原理,制作一个能够运转的发动机,就不那么容易了。

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