'Quick' and 'fast'

What is the difference between 'quick' and 'fast'? Is there any occasion in which one must be used rather than the other?

'Quick' and 'fast' have the same meaning. The difference is:

Adjective Adverb
fast fast
quick quickly

We usually add '-ly' to change an adjective to an adverb. However, 'fast' is both an adjective and an adverb, making it a special case!

e.g. Your daughter is quick.
e.g. Your daughter is fast.

e.g. Your daughter can run fast.
e.g. Your daughter can run quickly.

So, remember not to write 'fastly' when you actually mean 'quickly'!