Do you need/want some help?

Can I help you?

How can I help?

Would you like some help with that?

What do you need/want me to do?

You look like you need some help. 

Let me help you with that. 

A: Just let me know what you need. 如果你有什么需要，尽管告诉我。

B: Thanks. I really appreciate the help. 谢谢。我真的非常感谢你的帮助。

A: I'm here to help. Just let me know what you want.我是来帮忙的。尽管告诉我你需要什么。

B: I really appreciate this. 我真的非常感谢。

A: Would you care for some help with that?需要帮忙吗？

B: That would be great, thanks. 那真是太好了，谢谢。

A: Let me get that for you. 我来帮你拿吧。

B: Thanks. I thought I was going to drop it. 谢谢。我想我都快拿不住了。

A: Want/Need some help?需要帮忙吗？

B: It's about time. 

正是时候。