adj.有幫助的；有用的

You are very helpful. 您真幫了我的大忙。

These things are helpful for my life. 而且對我的生活是有幫助的。

These tactics are unlikely to be helpful to you. 這種方法對你未必有用。

adj.無用的；無益的；不給予幫助的；不予合作的

adv.有用地；有益地

n.有幫助；有益；有用