worth,worthy,worth-while都為adj. 意為"值得".

　　1. worth： be worth + n. 當名詞為金錢時,表示"…… 值得……"

　　be worth doing sth. "……某事值得被做"

　　The question is not worth discussing again and again.

　　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 againand again.

　　3. worth-while： be worth-while to do sth "值得做某事"

　　worth while： It is worth while doing sth

　　It is worth while sb to do sth.

　　典型例題

　　It is not ____ to discuss the question again and again.

　　A.worth B.worthy C.worth-while D.worth while

　　答案C. 由worth的用法可知,此句只適合詞組be worth-while to do sth..因此選C.

　　金額所有格+worth+of+某物:價值多少的某物

　　20 dollars's worth of good:價值20美圓的貨物。

　　worth doing sth.:值得做某事

　　sth. is worth doing. 某事值得做。