She really could not touch upon such an indelicate subject.

她实在不想触碰如此令人窘迫的话题。

Tis matter of small weight, my liege, yet will I touch upon it, an' it please your Grace.

这是件小事，皇上，但陛下如果愿意听，我就说一说吧。

And yet your touch upon them will not pass.

但你留下的触摸却不会消失。

Here I would like to briefly touch upon two major issues.

我现在主要介绍两个问题。

If they touch upon one another, one's mastery is sacrificed.

如果彼此触及，你的掌握被牺牲。