touch on

I want to touch briefly on another aspect of the problem.

我想简单地谈一下这个另一方面。

In his lecture on geology, he touched on the subject of climate.

他在关于地质学报中, 也涉及气候。

The article touched on the main problem.

文章提到主。

He touched me on the arm.

他碰了一下我手臂。

Such actions touch on betrayal.

这种行为近乎背叛。