give sb.a hand
给予某人帮助
A:What are you doing?
A:你在干什么?
B:I'm trying to put the vase on the shelf.
B:我想把这个花瓶放到架子上。
A:Let me give you a hand.
A:我来帮你一把。
B:No,thank you. I can manage it, I think.
B:不用了，谢谢，我想我能对付。