no
used as a reply
No can be a negative reply.
‘Is he down there already?’ – ‘No, he’s not there.'
‘Did you come alone?’ – ‘No. John’s here with me.'
No is a negative reply to negative questions. For example, if you are Spanish and someone says to you ‘You aren’t Italian, are you?', you say ‘No’. Don't say ‘Yes’.
‘You don’t like pasta, do you?' – ‘No’.
‘It won’t take you more than ten minutes, will it?' – ‘No’.
‘not any’
No is used in front of nouns to mean ‘not any’. For example, instead of saying ‘She doesn’t have any friends', you can say ‘She has no friends’.
I have no complaints.
My children are hungry. We have no food.
used with comparatives
No is used in front of comparative adjectives instead of ‘not’. For example, instead of saying ‘She isn’t taller than her sister', you say ‘She is no taller than her sister’.
The woman was no older than Kate.
We collected shells that were no bigger than a fingernail.
However, don't use ‘no’ and a comparative in front of a noun. Don't say, for example, ‘a no older woman’ or ‘a no bigger shell’.
used with ‘different’
No is used in front of different instead of ‘not’.
The local people say Kilkenny is no different from other towns.
‘not allowed’
No is often used on notices to tell you that something is not allowed. No is followed by an -ing form or a noun.
No smoking.
No entry.
No vehicles beyond this point.