worth， worthy， worthwhile都是形容詞，意為"值得".
1. worth： be worth + n. 當名詞為金錢時，表示"…… 值得……"
常見的有It ‘s worth while to do./ It ’s worth（someone‘s）while doing
be worth doing sth."……某事值得被做"
The question is not worth discussing again and again. 這問題不值得反復討論。
2. worthy：be worthy of +n.當名詞為抽象名詞時表示"……值得……"
be worthy to be done "某事值得被做"
The question is not worthy to be discussed again and again.
3. worthwhile： be worthwhile to do sth "值得做某事"
It is worthwhile to ask him to join the club.值得邀請他加入俱樂部。
典型例題
It is not ____ to discuss the question again and again.
A. worth B. worthyC. worthwhileD. worth while
答案C. 由worth的用法可知，此句只適合詞組be worthwhile to do sth.。選C.
