Cambridge Grammar of English Hardback with cd-rom a comprehensive Guide

Copular verb be

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In interrogatives, initial copular verb be is often not needed before you (and less

frequently we or they):

A: You all right for coffee, mum?

B: Yes, I’m all right, thanks.

(understood: Are you all right …?)

You sure you don’t want a lift?

(understood: Are you sure …?)

You the person who wanted a ticket?

We the people you were looking for?

They your friends or are they just people you work with?

In interrogatives, initial be and the subject may both be unnecessary before

adjectival complements:

[waiter to customers] 

Ready to order?

[host to child during a meal] 

Too spicy for you?

Declaratives: no subject pronoun   

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