If a place or substance is penetrable, you can move into it or through it.

The riverside bushes were certainly very thick, but the undergrowth behind was evidently penetrable. 河边的灌木当然很茂密，但后面的灌木丛显然是可以穿透的。

The barrier of poisonous gas appeared to be less penetrable than the rock that had been tunnelled through. 毒气屏障似乎比隧道穿过的岩石更难穿透。

If something such as a security system or device is penetrable, it is possible to get through or into it illegally in order to get information or do something illegal.

The U. S. airport security systems established in the early 1970s are penetrable by minimal ingenuity. 美国机场安全系统建立于1970年代早期，稍作努力便可渗透。

Everybody has a smartphone nowadays, and we are concerned about the safety of these vulnerable and penetrable devices. 如今，每人一部智能手机，这些设备防护薄弱、易于渗入，我们对其安全问题深感担忧。

If an area of business or a market is penetrable, you can become part of it and work in it.

The truth about this market has always been that it is penetrable, but only after tremendous effort. 事实上这个市场一直是可以渗透的，但必须经过巨大的努力。

able to be understood when studied or investigated

Parts of the book will be penetrable only by scholars. 本书的部分内容只有学者才能完全弄懂。

She will presumably be the ideal person to help make the young doctor's prose more penetrable. 她大概是理想的人选，可以帮着弄懂这位年轻医生的文字。