n.救生索；生命線

He threw me a lifeline when he offered me a job. 他給我工作就相當(dāng)于拋給了我一條救命索。

He clung to the lifeline and the woman pulled him towards the bank. 他緊緊抓住救生索，那個女人把他拉向岸邊。

Public transport is a lifeline for many rural communities. 公共交通對許多農(nóng)村居民來說是不可或缺的。