And, of course, a four - or, preferably, five-gas analyzer is a must for anyone doing serious emissions work.

当然，四气体或最好五气体分析仪，是任何人认真做好排放量测试工作的必需品。

youdao

And, of course, a four - or, preferably, five-gas analyzer is a must for anyone doing serious emissions work.

当然，四气体或最好五气体分析仪，是任何人认真做好排放量测试工作的必需品。

youdao