1.worth adj&n.值得,应该,作形容词在句中只能作表语
①sb./sth.be worth ...:
His words are worth notice.他的话值得注意.
The bike is worth 200 yuan.
②be (well) worth doing (很)值得做...,注意这个句型是主动表被动的用法,如这本书值得一读
This book is worth reading.
2.worthy adj&n.有价值的,值得...的,做形容词时既可以做表语又可以作定语
①be worthy of +n.
He is worthy of our praise.
②be (quite)worthy of being done (很)值得做...:
The film is worhty of being watched.
③be worthy to be done (很)值得做...,上面的句子可以改写为:
The film is worthy to be watched.
3.worthwhile adj.值得做的..值得出力的,既可以做表语又可以作定语
be worthwhile doing/be worthwhile to do:
It is worthwhile discussing the question again.=It is worthwhile to discuss the question again.