:thought_balloon:Would is used to talk about unreal situations in the present or past, could expresses possibilities in the present, and should is used to give advice or express obligation.
:speech_balloon:When using would or could, contraction is commonly applied, such as using I'd instead of I would or he'd instead of he would.
:question:Would and could can also be used to report past intentions or express past ability, while should is used to indicate the correct or recommended course of action.
:arrow_right:In unreal situations in the present, would is often used with if statements, such as 'If I were you, I would go to the doctor.'
:closed_lock_with_key:When using would or could in the past tense, 'have' is added before the past participle of the main verb, such as 'If I had known, I could have helped you.'