1.healthy作形容词的基本意思是“健康的,健壮的”,指人的身心处于良好的状态,很少生病。引申可作“(事物)兴旺发达,发展良好”解。
2.healthy不能用来表示一时的健康,而是指一个长期的状态或过程。

用作定语
▲～+n.
He is a very healthy boy.他是个很健康的男孩。
He is a man of healthy build.他身体健壮。
A healthy man is not conscious of his breathing.一个健康的人是不会意识到自己的呼吸的。
Some researchers contend that carcinogens may turn healthy cells into cancer cells.有些研究人员认为,致癌物质能使健康细胞变成癌细胞。
You should take plenty of healthy exercises.你该多参加些有益于健康的运动。
The healthy air at the seaside is good for you.海边有益于健康的空气对你有好处。
Children need healthy food.儿童需要有益于健康的食物。
The child showed a healthy curiosity.这个孩子表现出一种与生俱来的好奇心。
The healthy appearance of the children is eloquent of the wealth of the nation.孩子们健康的精神面貌充分表明了该国的富足。
She has a healthy appetite.她胃口好。
用作表语
▲S+be+～
That boy looks handsome and healthy.那男孩看上去英俊而健康。
I am as healthy as ever.我依然那样健康。
Their children are well-fed, active and healthy.他们的孩子都喂养得很好,活泼而又健康。
That book is not healthy reading for a child.那本书很不健康,不适宜孩子阅读。
The country's economy is not very healthy.国家的经济不很景气。

healthy, healthful
这两个词的共同意思是“健康的”。其区别是:healthy着重指身心处于良好的状态,用作表语或定语都可以; healthful是有益于身体的意思,多半用来修饰气候方面的情况,而以用作定语为多。例如:
 We have a healthful climate here.我们这儿气候宜人。
healthy, fit, well
这三个词都可以表示“身体健康”。其区别是:healthy侧重有益于健康的条件或者是健康人的外部征象;fit指人的身体状况良好,尤其是指因经常锻炼而显得健康;well一般指人在特定场合下身体良好,常用来回答有关健康的询问。例如:
He stays so fit because he often goes to keep-fit classes.他之所以能保持健康是因为他经常去上健身课。
I think I'll go to bed. I don't feel well at all.我要睡觉去了,我感到很不舒服。
healthy, hale, robust, sound, well
参见sound条。

［同义词］   active, beneficial, fine, fit, good, hardy, healthful
［反义词］   diseased, ill, infirm, sick, unhealthy, weak