worth，worthy，worthwhile都为adj. 意为值得。
1. worth：be worth + n. 当名词为金钱时，表示…… 值得……
be worth doing sth. ……某事值得被做
——I had to pay ten dollars for this book.
——It’s probably worth it.
我不得不花了十美元买了这本书。
它或许值这个钱。
The question is not worth discussing again and again.
这个问题不值得反反复复讨论。
2. worthy：
be worthy of +n. 当名词为抽象名词时表示……值得……
be worthy to be done. 某事值得被做
The question is not worthy to be discussed again and again.
这个问题不值得反反复复讨论。
He felt he was not worthy of her.
他觉得他配不上她。
The Minister says the idea is worthy of consideration.
部长说这个想法值得考虑。
另外worthy可作定语：
The money we raise will be going to a very worthy cause.
我们筹集的钱款将用于非常崇高的事业。
That's a worthy task.
那是一项很有价值的工作。
When we die for the people; it is a worthy death.
我们为人民而死，就是死得其所。
Travel gives us a worthy and improving pleasure.
旅行给予我们一种高尚有益的快乐。
3. worthwhile：be worth-while to do sth 值得做某事
注意： worthwhile= worth while
worth while：
It is worth while doing sth
It is worth while sb to do sth.
It is not worthwhile to discuss the question again and again.
这个问题不值得反反复复讨论。（不定式或动名词作真实的主语）
It’s not worth while losing your temper.
你不值得发脾气。（动名词作真实的主语）
It’s not worth your staying.（动名词作真实的主语）
你不值得留下来。