Suggestions and obligations

Learn how to use different modal verbs to make suggestions and to speak about obligations, and do the exercises to practise using them.

Level: beginner


We use should and shouldn't to make suggestions and give advice:

You should send an email.
You shouldn’t go by train.

We also use could to make positive suggestions:

We could meet at the weekend.
You could eat out tonight.

Level: intermediate

We can use conditionals to give advice:

Dan will help you if you ask him.

Past tenses are more polite:

Dan would help you if you asked him.

Suggestions 1


Suggestions 2


Level: beginner


We use must or need to to say that it is necessary to do something:

You must stop at a red light.
Everyone needs to bring something to eat.
You can wear what you like, but you must look neat and tidy.

We use mustn't for prohibitions – to say that it is necessary to not do something:

You mustn't make any noise in the library.
You mustn't say anything to her. It's a surprise.

We use had to (positive) and couldn't (negative) if we are talking about the past:

Everyone had to bring something to eat.
You couldn't make any noise in the library.

Obligations 1


Obligations 2



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Submitted by howtosay_ on Thu, 22/12/2022 - 01:35



As far as I know, we are to use "Should" in questions, but what if situation refers to "must" or "have to"? Could I ask "Must you be silent?" or "Do I have to be silent?" or "Have I got to be silent?", for example. And if the question is "Should we send an email", might the answer be "We must" or "We have to".

And one more question. I'm sorry, but I'm very curious about the sentence "We use mustn't for prohibitions – to say that it is necessary TO NOT DO something". Do you say "It is necessary NOT TO DO something" or is it a mistake?

I'm so much grateful for your work, and thank you very much for your answer beforehand!!!

Hello howtosay_,

There's no reason why you can't use modal verbs in questions - should is not special in this regard. Generally, 'have to' is preferred in questions as 'must' sounds much more formal and even old-fashioned, but grammatically both are fine.


Both 'necessary to not do' and 'necessary not to do' are fine. I think the former is more common, but this may be a question of dialect.



The LearnEnglish Team

Profile picture for user Ahmed Imam

Submitted by Ahmed Imam on Tue, 22/11/2022 - 09:10


Hello. Could you please help me? Which one is correct?

- A: What is the rule about visiting people in hospital?

B: You (must - have to) go between 2 and 5 o'clock in the afternoon.

Thank you.

Hello Ahmed Imam,

It'd be more natural for B to say 'Visiting hours are between ...' or 'You can only go between ...' here. If you're testing the difference between 'must' and 'have to', I'd recommend writing a different sentence.

All the best,
The LearnEnglish Team

What about the following sentence: - I (must - have to) be at home before 10 pm. That's a family rule.
Thank you.

Hello Ahmed Imam,

I'd say 'have to' is better here since it sounds like an external obligation. In general, we prefer 'have to' to talk about obligations imposed by external rules. 'must' can be used to give strong orders to others and it is often used to talk about what one feels one needs to do, though, so it's also possible.

Hope this helps.

All the best,
The LearnEnglish Team

Submitted by g-ssan on Fri, 14/10/2022 - 20:44


Sir ,
Does should use in obligation ? i imagine it has same meaning with must and ought to . Am I right ? .

Hello g-ssan,

Generally, should and ought to express advice rather than obligation. These verbs imply that there is a choice, whereas must suggests that there is no choice. Of course, such meanings are very much dependent on the context in which the words are used.



The LearnEnglish Team

Submitted by g-ssan on Fri, 14/10/2022 - 19:42


Hello sir ,
Are need to and had to modal verb ?
Why they took (s) third person in example above "every one needs to bring something to eat "?
Correct me if I am wrong please ?

Hello g-ssan,

These are examples of what are sometimes called semi-modal verbs, which means verbs which have some features of modal verbs but not all. In some cases they are verbs which are in the process of changing their form over time. For example, questions and negatives with 'need' are generally formed with 'do':

Does he need to come in person?

You don't need to finish it today.

However, you can use full modal forms:

Need he come in person?

You needn't finish it today.

These forms are becoming less common and will eventually, probably, disappear from the language. It's an example of the language evolving before our eyes.

You can read more about need as an example here:



The LearnEnglish Team

Submitted by Faii on Mon, 25/07/2022 - 08:41


"It was going to be a long day.I was supposed to clean up all the stables,and then start on the garden"

Is it clear from here that I have done the things I was suppose to do ?

Hello Faii,

No, it's not. This sentence does not tell us whether or not the speaker did or will do those things. It tells us how the day looked at the start, not what happened after that. Perhaps the speaker did all of those jobs, or perhaps they decided to leave everything and take the day off instead. This sentence does not tell us.



The LearnEnglish Team

Submitted by Mayura on Sun, 26/06/2022 - 16:48


Hello, Sir.
I wanted to know if "should have to" still expresses "advice". Are the 3 sentences the same in meaning, especially 2 and 3.
1. You should do exercise every day to be fit.
2. You should have to do exercise every day to be fit.
3. You had better do exercise every day to be fit.
Best Wishes!

Hello Mayura,

'Should have' expresses advice in the sense of identifying a better alternative in the past which was not taken. For example, I go to the restaurant and order a pizza, but the pizza is not good so I think 'I should have ordered lasagne!'

The form is should have + verb3 / past participle (should have ordered).


Your examples do not contain 'should have' in this form.

The first sentence describes advice about the present (specifically, general time): should + base form (should do)

The second sentences also uses should for present time. The verb here is 'have to', which is not a past participle: should + have to + verb (should have to do). It has the same meaning as the first sentence with the addition on obligation.

The third sentence gives advice about the future. It does not describe advice in general but rather what the listener should do in the future. Thus, it gives advice but has a different meaning to the first sentence. The form here is had better + verb (had better do).



The LearnEnglish Team

Submitted by HieuNT on Tue, 18/01/2022 - 19:42


Hello, British Council Team,

In famous grammar books or online dictionaries, I didn't see any reference to the use of of "should not" after "suggest".

However, I've seen this structure widely used in this way.

E.g.: "What we won't see, however, is politicians suggesting that we shouldn't have a National Health Service."


My question is: Is this phenomenon considered "Standard English", or it's just the same case as double/multiple negatives which is acceptable in informal contexts only because they are commonly used but are inappropriate in more formal contexts?

Should I use "should not" this way or should I stick to the subjunctive (not + infinitives) when it come to negative suggesting sentences?

Thank you, and I hope to hear from you soon.
Hieu Nguyen

Hello Hieu Nguyen,

You're correct that we don't use suggest + should (not). Suggest can be followed by a that-clause which includes 'should', however, and this is what your sentence is an example of:
> She suggested that we shouldn't have a National Health Service.

Other modal verbs can be used:
> She suggested that we couldn't have a National Health Service unless we raised taxes.
> She suggested that we mightn't have a National Health Service in the future.

A verb-ing form is also possible and is used when making a proposal:
> She suggested not having a National Health Service. Instead, ...

And, as you say, the subjunctive form is also an option, though it tends to be used in more formal contexts:
> She suggested that we not have a National Health Service.

The LearnEnglish Team

Hello Mr. Peter,

Thank you for your explanation.
However, I believe the way I put my ideas was not clear.

I know that "suggest" cannot be followed directly by "should (not)", as in:
>She suggested shouldn't have a National Health Service.

What I was asking is, is it standard English to use "should (not)" in "suggest + that clause" or is it a habitual use (like double negatives) which then become acceptable in informal contexts, as in:
> She suggested that we shouldn't have a National Health Service.

Hieu Nguyen

Hello again Hieu Nguyen,

It's fine to use 'should not' like this. Your example is perfectly correct and in no way non-standard.

The LearnEnglish Team

Thank you for your clarification, Mr. Pete.

Normally, I would only use "should not" after "suggest" to mean "show" or "express", as in:
> The result suggests that we shouldn't...

Now, I think I'll start using "should not" after "suggest" when I make a recommendation or give someone else advice in some case without worrying too much.