Some words can be used interchangeably without changing the meaning of the sentence, but some can be used interchangeably but affect the meaning of the sentence. Should and Must are two similar words that can be used interchangeably in a sentence, but both of them mean different in a sentence.
Should vs Must
The main difference between Should and Must is that Should is the past form of shall, and it is an auxiliary verb used in a sentence to give suggestions or advice, whereas Must is also an auxiliary verb, but it is used in the sentence to suggest what is compulsory to be done.
Should is the past form of shall, and it is used as an auxiliary verb in a sentence. It is used in a sentence to give suggestions or advice and also to ask for advice or suggestions. It can be used in present tense sentences as well as future tense sentences.
Must is also an auxiliary verb. It is used in sentences that are necessary or if you are sure about something to be true and for a strong recommendation. It shows obligation and used to give suggestions that are compulsory to be done. It is also used in law and orders sentences to show obligations.
Comparison Table Between Should and Must
| Parameters of Comparison | Should | Must |
| Meaning | It is the past form of shall that indicates duties or responsibilities. | It is a modal verb that indicates necessity or a task that needs to be executed. |
| Nature | It is informal in nature. | It sounds formal when used in sentences. |
| Use | It is used to give or ask for suggestions and advice. | It is used to show obligations. |
| Degree of Emphasis | It shows less emphasis in the sentence. | It shows more emphasis in sentences. |
| Example | I should go to school. | We must follow traffic rules. |
What is Should?
Should is a modal verb, and it is used with other verbs to give suggestions or ask for permissions. It is the past form of Shall but used in different sentences other than the past form of Shall. Should when used in the sentence shows responsibilities, duties, or the thing that is right to do.
It is used as epistemic modal and also as deontic modal, as ‘should’ is used to give suggestions and also to ask for permissions. It is used to show probability and sometimes expectations. It is also used sometimes to express obligations but express less emphasis. There are many other uses of should in sentences.
Let’s discuss and see examples of uses of Should:-
- It is used to tell or ask for the best choice from all available options. For example, You should do yoga instead of running and cycling.
- It is used to show some chances of happening something. For example, She should be in the market at this time.
- It is used to ask or give a reason for something. For example, Why should I do yoga instead of running and cycling?
- It is used to give advice. For example, You should meet her at CCD in the evening.
Other than these examples, Should is used in many types of sentences that we can learn by practising in daily life.
What is Must?
Must is also a modal verb and acts as a helping verb in the sentences. It is used to express obligations, and in sentences, it shows the necessity and tells what has to be done. Must is used formally in many sentences to give suggestions and also used in sentences to tell any rule of law.
It can be used interchangeably at the place of should without producing any grammatical mistakes, but it would change the context of sentences. It will make a suggestion into an obligation. When used in sentences, it emphasizes the importance or need of the object.
Let’s discuss and see examples of uses of Must:-
- It is used to express an object’s importance or necessity. For example, You must have protein in your diet.
- It is used in sentences to apply prohibition. For example, You must not make noise in the class.
- It is used to emphasize anything in the sentence. For example, You must tell her that she is very hard working.
- It is used to express strong action. For example, He must be the CEO of this company.
These are just a few examples. There are many other uses of Must that we can learn and practice in our day-to-day use.
Main Differences Between Should and Must
- The main difference between Should and Must is that Should is used in a sentence to give suggestions or ask permission, whereas Must is used in a sentence to express obligations or show necessity.
- Should is used informally in sentences. On the other hand, Must is a formal way of expressing something in a sentence.
- Should show responsibilities and duties when used in a sentence but Must expresses importance like an important law or rule.
- Should and Must can be used interchangeably, but if we use Should in a sentence, it will be a suggestion, and if we use Must instead of Should in the same sentence, it will be a compulsion task.
- ‘Should’ is used to show a chance, ask permission, give advice, etc. On the other hand, ‘Must’ is used to express obligations, apply prohibition, express strong action, etc.
Conclusion
The English language is an internationally accepted language. It is simple to learn but has many words that confuse many learners, words could be used interchangeably, but it can affect the context of sentences. So we should learn the proper meaning and usage of confusing words.
Shall and Must are modal verbs used as helping verb in the sentence. Both of the words have different uses and different from each other in many ways. Shall is used to suggest someone or seek permission and ask for advice. But Must is used to show the necessity of the task at that moment. It can be used to express strong actions as well.
References
- https://heinonline.org/hol-cgi-bin/get_pdf.cgi?handle=hein.journals/aklr43§ion=38
- https://academic.oup.com/slr/article-abstract/41/1/89/5203269