Use of these chemicals may present a fire risk.

　　使用這些化學品可能有失火的危險。

　　When did this word come into common use?

　　這個詞是什么時候普遍使用起來的？

　　All the materials used were of the highest grade.

　　使用的材料全是優質品。

　　This door should only be used in an emergency.

　　這道門只能在緊急情況下使用。

　　The bar is for the use of members only.

　　酒吧僅供會員使用。