adj.有帮助的；有用的
You are very helpful. 您真帮了我的大忙。
These things are helpful for my life. 而且对我的生活是有帮助的。
These tactics are unlikely to be helpful to you. 这种方法对你未必有用。
adj.无用的；无益的；不给予帮助的；不予合作的
adv.有用地；有益地
n.有帮助；有益；有用
