用作定语
▲～+n.
This book is designed to be provocative rather than a watertight piece of economic analysis.这本书旨在引起争论，而不是对经济作严密分析。
用作表语
▲S+be+～
The boat is watertight.这条船不漏水。
The medical argument against this substance is, however, not watertight.然而，反对这种材料的医学争论并不是无懈可击的。
用作宾语补足语
▲S+V+O+～
Its bow torpedo doors have had to be locked to keep the submarine watertight.它前部的鱼雷门不得不锁上，以使潜水艇不漏水。