You should go to that party. It’s going to be really interesting. —
His landlord asked him to move out so he has to look for a new apartment.
He doesn’t have to cook because his mom comes to him and does cooking. He shouldn’t cook for the party because nobody likes his dishes.
You should go to this exhibition, I think. You must go to this exhibition. It’s very useful!
You mustn’t use someone’s ideas in your book without any references. It’s plagiarism.