1
general::
Phrase(s): How may I help you? [and] How can I help you?; How can I serve you?; May I help you?; What can I do for you?
In what way can I serve you? (Usually said by store clerks and food service personnel. The first question is the most polite, and the last is the least polite.) • Waiter: How can I help you? Sue: I’m not ready to order yet. • Clerk: May I help you? Jane: I’m looking for a gift for my aunt.
McGrawhill's American Idioms And Phrasal Verbs