1 With how (rather formal)
how + adjective |
Strawberries! How nice!
How + adjective/adverb + subject + verb |
How cold it is! (NOT –How it is cold!)
How beautifully you sing! (NOT –How you sing beautifully!)
how + subject + verb |
How you’ve grown!
2 With what
what a/an (+ adjective) + singular countable noun |
What a rude man! (NOT –What rude man!)
What a nice dress! (NOT –What nice dress!)
What a surprise!
What (+ adjective) + uncountable/plural noun |
What beautiful weather! (NOT –What a beautiful weather! (NOT What a beautiful weather!)
What lovely flowers!
3 Negative questions
Isn’t the weather nice!
Hasn’t she grown!
In American English, ordinary (non-negative) question forms are often used in exclamations.
Am I hungry! Did she make a mistake!