The content systematically explores should as a fundamental modal auxiliary verb that serves three primary functions: expressing advice and recommendations, indicating mild obligation or responsibility, and conveying expectations about future events or logical deductions. The meaning of SHOULD is —used in auxiliary function to express condition —usually used with if. How to use should in a sentence. The main verb can never be the to-infinitive. We cannot say: He should to go. There is no short form for should, but we can shorten the negative should not to shouldn't. Sometimes Should is used instead of Must to make rules, orders or instructions sound more polite. This may appear more frequently on formal notices or on information sheets. You should [= ought to] get some rest. They should be punished. We should leave a few minutes early to make sure we get there on time. SHOULD definition: must; ought (used to indicate duty, propriety, or expediency). See examples of should used in a sentence. The meaning of SHOULD in English with example sentences. Learn English modal verbs - Should vs Ought to Learn how to use the English verbs should, must, and ought to. Get clear, simple grammar advice from expert English teachers at the British Council. We use the full form should not in formal contexts or when we want to emphasis something: We should not forget those who have given their lives in the defence of freedom. SHOULD definition: 1. used to say or ask what is the correct or best thing to do: 2. used to show when something is…. Learn more.