Cleaning of gas is difficult and Labour intensive process.

天然气清洁是困难的，劳动密集的过程。

youdao

We all know what the difficult was. There was no need to labour the point.

我们都知道困难是什么，没有必要再细说了。

youdao

We all know what the difficult was. There was no need to labour the point.

我们都知道困难是什么，没有必要再细说了。

youdao