touch on

The article touched on the main problem.

文章提到主要问。

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

简单地谈一下这个问的另一方面。

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

关于地质学的报告中, 也涉及气候问。

He touched me on the arm.

一下的手臂。

Such actions touch on betrayal.

这种行为近乎背叛。