关于他的事我早就听说过了。

I heard about his affairs long ago.

关于这一点你可以放心。

You can relax on that score.

关于养蜂的书

book on beekeeping

关于哲学的知识

knowledge about philosophy

关于国际形势的报告

report on the international situation

关于国际工运的问题

question about the international labour movement