有用的的用法和樣例：
例句
-
這是有用的書，更難得的是不貴。
It is a useful book and, what is more, not an expensive one. -
有點依靠的東西總是有用的。
It's always useful to have something to fall back on. -
向他解釋理由是沒有用的。
It is no use explaining the reason to him. -
這會非常有用的。
It'll be most useful. -
她是個應該結交的有用的人。
She is a useful person to know. -
跟他們討論終止合同是沒有用的。
It's no use to discuss the termination of contract with them. -
約翰經常設法和對他有用的人結交。
John always tries to cultivate people who are useful to him.
