Linda shouldn't drink alcohol; it's not good for her.
We shouldn't make any noise in order not to wake the baby up.
You should eat vegetables every day.


 

Linda shouldn't drink alcohol: it's not good for her.
We use "shouldn't" to express advice or a recommendation.
We must not make any noise in order not to wake the baby up.
"Must not" is used to express strong prohibition.
You should eat vegetables every day.
"Should" is used to give advice or recommendations.