Would

1. would is commonly used in, if sentences when referring to imaginary or improbable situations about the present or future
Eg. we would stay longer if we had more time
how would you feel if someone gave you $ 1, 0000

2. [COLOR='00BFFF']w[/COLOR][COLOR='2194F0']o[/COLOR][COLOR='4169E1']u[/COLOR][COLOR='2135F0']l[/COLOR][COLOR='0000FF']d[/COLOR] can be used to express repeated or habitual past actions, and is similar in meaning to [COLOR='00BFFF']u[/COLOR][COLOR='16A2F5']s[/COLOR][COLOR='2B86EB']e[/COLOR][COLOR='4169E1']d[/COLOR][COLOR='2B46EB'] [/COLOR][COLOR='1623F5']t[/COLOR][COLOR='0000FF']o[/COLOR]
Eg. when we were living in the country, we would collect mushrooms from the forest

however, [COLOR='00BFFF']w[/COLOR][COLOR='2194F0']o[/COLOR][COLOR='4169E1']u[/COLOR][COLOR='2135F0']l[/COLOR][COLOR='0000FF']d[/COLOR] and [COLOR='00BFFF']u[/COLOR][COLOR='16A2F5']s[/COLOR][COLOR='2B86EB']e[/COLOR][COLOR='4169E1']d[/COLOR][COLOR='2B46EB'] [/COLOR][COLOR='1623F5']t[/COLOR][COLOR='0000FF']o[/COLOR] are not interchangeable when talking about past states
Eg. when I was younger I used to have long hair

here, only [COLOR='00BFFF']u[/COLOR][COLOR='16A2F5']s[/COLOR][COLOR='2B86EB']e[/COLOR][COLOR='4169E1']d[/COLOR][COLOR='2B46EB'] [/COLOR][COLOR='1623F5']t[/COLOR][COLOR='0000FF']o[/COLOR] can be used and would is not possible

3. in the negative form, wouldn’t can be used to express a refusal or unwillingness
I asked her nicely, but she wouldn’t help

It is also used with inanimate objects
Eg.-- The car wouldn’t start this morning
--I gave it a push but the door still wouldn’t open

4. would is used as the past tense of will in reported speech
Eg. --She warned us that it would be dangerous
--He told her it would cost a lot of money