Can I help you ? 我能帮你吗?
What can I do for you ?或May I help you ?,作为对顾客的招呼语。
eg: --Can I help you?
--Thank you . I want some bananas, please.
小练习:排列顺序
( ) I’d like a pair of socks.
( ) How much are they ?
( ) Can I help you ?
( ) Ten yuan.
Expressions