水管工检查了阀门，发现需要更换新的垫圈。

The plumber checked the valve and found that new ___gaskets were needed.

更换水管连接处的密封垫可以防止漏水。

Replacing the ___gaskets at pipe joints can prevent water leakage.

发动机漏油了，我们需要更换新的垫片。

The engine is leaking oil, so we need to replace the ___gaskets.