A) We use rather as an adverb of degree:
Modifying an adjective:
The film was rather good.
Modifying an adverb:
It happened rather quickly.
It is stronger than fairly, but not as strong as very.
- It can modify a noun, often coming before the article:
It's rather a problem.
It can modify some verbs: I rather like it.
B) To express preference
Rather than is normally used to compare parallel structures:
Let's take the train rather than the bus.
Rather you than me!
I decided to write rather than email.
Would rather + infinitive without 'to':
Would rather + pronoun + past tense:
I'd rather he came early.