should (third-person singular simple present should, no present participle, no simple past or past participle) (modal, auxiliary, defective) Ought to; indicating opinion, advice, or instruction, about what is required or desirable. The simple definition of SHOULD is —used to say or suggest that something is the proper, reasonable, or best thing to do. The meaning of SHOULD is —used in auxiliary function to express condition —usually used with if. How to use should in a sentence. SHOULD meaning: 1. used to say or ask what is the correct or best thing to do: 2. used to show when something is…. Learn more. 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. 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. Find out how to use the modal verb 'should'. We'll also study the question form and the negative. SHOULD definition: must; ought (used to indicate duty, propriety, or expediency). See examples of should used in a sentence. This article explains the use of should in sentences in English grammar. It also describes the use of should, use of shall, and would and use of ‘should have’. Usage: Should has, as its most common meaning in modern English, the sense ought as in I should go to the graduation, but I don't see how I can. However, the older sense of the subjunctive of shall is often used with I or we to indicate a more polite form than would: I should like to go, but I can't.