请求帮助时，Can you 和 Could you 放在动词前面，Would you mind 放在 -ing 词前面。跟不太熟的人说话时用 Could you，跟朋友说话时用 Can you。
请求帮助
Can you — Can you help me with this bag?
Could you — Could you open the door?
Would you mind — Would you mind holding this?
试一试: Mei: ___ help me with this heavy bag? Lars: Of course. Let me take it. Mei needs help and wants to ask Lars politely. Which fits? (Could you / Let me / Shall I) 答案: Could you — Could you 是礼貌地请人帮忙的说法，正是 Mei 需要的。Let me 和 Shall I 是用来主动提供自己的帮助，都不是在请 Lars 做什么事。
主动提供帮助
想主动提供帮助时，如果你打算直接动手做，就在动词前用 Let me；如果想先问一下，就用 Shall I；想表达一种体贴周到的提议，就用 Would you like me to。
Let me — Let me carry that for you.
Shall I — Shall I call a taxi?
Would you like me to — Would you like me to help?
试一试: Camila: I can't reach the top shelf. Farid: ___ get it for you. Choose the offer that means Farid will do it himself. (Let me / Could you / Would you mind) 答案: Let me — Let me 表示 Farid 会自己动手做，正合适。Could you 和 Would you mind 都是在请 Camila 做什么事，都不是在主动提供帮助。