worth,worthy,worth-while都為adj.意為"值得".
1.worth：be worth + n.當(dāng)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(dāng)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.
ps：至於reading做什么 我不太清楚,be worth doing 是一種固定搭配后面的做什么成分啊？sorry啊，不是我不想幫你，是我真的無能為力啊，我不知道后面的做什么成份，我?guī)湍闳タ戳艘幌抡Z法書，但上面也沒說那個doing做什麼成份。