Would, could and might

The modal auxiliary verbs would, could and might also make questions, orders and suggestions more polite.

I think it would be better to paint it yellow. (More polite than ‘It will be
better to paint it yellow’.)
Could you help me? (More polite than ‘Can you help me?’)
I was wondering if you might be interested in watching a movie.

Would is very often used with verbs like prefer and like.

What would you like to drink?
Would you like to come with us?

Yes / no questions

Requests and statements can be made more polite by putting them in the form of yes/no questions.

Could you pass the salt, please? (More polite than ‘Please pass the salt.)

Statements can also be made more polite by turning them into questions.

Compare:

It would be nice to go for a walk. (Direct expression of opinion)
Wouldn’t it be nice to go for a walk? (Persuasive question – less direct)
Would it be better to go for a walk? (Open question – very indirect)

Conditional and negative expressions
Conditional and negative expressions are also used to make suggestions sound less direct.

What if we went for a walk? (Less direct than ‘Can’t we go for a walk?’)
It would be better if you would come over and introduce yourself. (More
polite than ‘Please come over and introduce yourself.’)
If you would come this way, we could go for a long drive.