现在完成进行时的英文怎么说

现在完成进行时的英文：
present perfect progressive

There is at present uncertainty regarding the hazard to health presented by crocidolite.
目前，青石棉对健康的危害尚不清楚。

Some diseases are presented by heredity.
有些疾病是由于遗传导致的。

should alternately present as undulate .
激情平淡应呈波浪形交替出现。

It was not a perfect system.
它不是一个完美的系统。

There are a few disadvantages that take from the perfection of the perfection of the garden.
有几个不利条件使得花园不够完美。

There was a perfect rage for demolition.
这简直是一场疯狂的破坏。

progressive tense
ph.1. 【语】进行时态,进行式

innovative progress
开拓进展

The road construction work is in progress.
筑路工程正在进行中。