那如果有其他方法让发动机运转又会怎么样呢？

But what if there were another way to make engine parts move?

youdao

大多数发动机运转为四行程循环。

Most automobile engines operate on four stroke cycle.

youdao

飞轮通过本身的质量使发动机运转平稳。

Because of its weight, the flywheel helps to smooth engine operation.

youdao

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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