Where are the children?

A guest visited me asked the above question. I told him the following:

1) They must be playing in the garden now.

I said the above as I am certain that they are playing with the neighbour's children in the garden.

How about the following sentence?

2) They should be playing in the garden now.

I believe the first and the second sentences have no difference in the meaning; so I could simply use the second sentence.

What do you think?
There is a slight difference in meaning in that (1) has more certainty attached to it.

(1) You just walked past the garden and saw the children there, and you told them that they are to stay in the garden until supper time. So "they must be playing in the garden." Unless, of course, they ignored your instructions and left very quickly. "Must" infers some sort of obligation. See at the end of this message.

You could also drop the "must" and simply say, "They are playing in the garden." This is how I would say it.

(2) You served the children lunch about a half hour ago, and the children said that they were going to the garden for a while, say an hour or so, and then later they were going to the playground. So they should be playing in the garden now, but if they are not there, they are probably at the playground.

Do you see the difference in certainty? "Must" is very strong.

Using GuruNet....



To be obliged or required by morality, law, or custom: Citizens must register in order to vote.
To be compelled, as by a physical necessity or requirement: Plants must have oxygen in order to live.
Used to express a command or admonition: You must not go there alone. You simply must be careful.
To be determined to; have as a fixed resolve: If you must leave, do it quietly.

Used to indicate inevitability or certainty: We all must die.
Used to indicate logical probability or presumptive certainty: If the lights were on, they must have been at home.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2003 by Houghton Mifflin Company.
Hello, Andrei Emotion: smile

Let me post something to avoid misundertanding in this thread.

"Must" is a common modal verb.
It does not always imply obligation. This is just what we teach our beginner students because it makes learning easier for them.

But "must" is also widely used to show a "belief" or "deduction".

Have a look at the following example:
"Sue said she would still be here by when I got back from work, but I've looked for her everywhere and couldn't find her. She must have gone to the store."

If Sue was expected to be in a certain place at a certain time, but she was not there, then it is not possible to say, or even think or "understand" from these sentences that it was her "obligation" to leave.
Rather, the speaker is expressing a "belief" or making a "deduction". There is no order or command implied in "must" as it is used in the example.

Another example: "I can't find my keys; I must have lost them."
It would be very funny to think that I had the "obligation" to lose my keys!!
So, by using "must" in the above sentence, I am only saying that I believe I have lost the keys.

In "The children must be playing in the garden", you have to be careful. It is obvious that "must" may imply either meaning unless you provide some context. Yet, it is not possible to say, with any certainty, that "must" implies "obligation" in this sentence.

One interpretation of the above sentence is: "I believe they are playing in the garden."
Another possible interpretation is "they have the obligation to be playing in the garden now", but it is not the first meaning that would come to the reader's mind... unless you provide a suitable context for that meaning in particular.

"Should", on the other hand, when it is used instead of "must" (in the sense of "obligation"), is less strong that "must" and may be understood also as "strong advice".
For example:
"It's 7:30 already, the children should be getting ready for school (or else, they will be late)."

"Should", in your example "The children should be playing in the garden", may be understood as "advice" or "suggestion" as well:
"It is a sunny day. Why are the children in the living-room? They should be playing in the garden."

Now, "should" still in your sentence about the children being in the garden may even be understood as having similar meaning to "must" when "must" means "deduction":
Suppose you saw the children playing in the garden 10 minutes ago. Now you're in the kitchen, and your wife comes in and says "Where are the children? They aren't in the living-room."
You could respond "They should be playing in the garden", since that is where you saw them only 10 minutes ago and perhaps you see no reason to believe they are somewhere else now.

Teachers: We supply a list of EFL job vacancies
Thanks MountainHiker

If you see an intruder in your garden, you could say either 'you must leave the garden immediately' or 'you should leave the garden immediately'.

I feel in the above case you are free to use either must or leave and it has no difference in the meaning. What do you think?
If you are bigger, stronger, and meaner than the intruder, say "You must leave the garden immediately."

If you are smaller, weaker, and kinder than the intruder, say, "Please, you should leave the garden immediately."

The above is a bit humorous. In reality, you could probably use either, though I would tend to use "must." It depends, too, if the person is there meaning harm or by mistake. If the person means harm, you want to be firm. "Must" is probably a better choice. If the person happened to be there by error, "should" is more polite and cordial.

You could use "should", too, for those more serious situations, but with a tone in your voice that suggests serious consequences should the person ignore your request.

You could also say, "Leave now or I'm calling the cops (or whatever you want to do to bolster your position).

In general, consider "must" more forceful and serious than "should".

I hope that helps.
Site Hint: Check out our list of pronunciation videos.
"I believe the first and the second sentences have no difference in the meaning; so I could simply use the second sentence."

It really depends on the context. If someone asked, "Where are the children?" then I agree with MountainHiker's examples. However, if someone said, "The children aren't in the living room," you could reply, "They must be in the garden," as in, if it's not one thing, it's the other. Another example, if the person is not male, then they must be female. Correct? If you responded with, "They should be in the garden," that would imply that they weren't ever supposed to be in the living room because they were told to be in the garden. Therefore, the words would imply two different meanings.

"I feel in the above case you are free to use either must or leave and it has no difference in the meaning. What do you think?"

I believe you meant you are free to use either must or should. In this case, there is also a different. By saying "You must leave the garden," you are making an order. By not leaving the garden, they are disobeying an order and will most likely receive a consequence. If you said, "You should leave the garden," it's a suggestion. They don't have to leave the garden - it just might be a good idea. Once again, the words would imply two different meanings.

Edited by moderator
Please, do avoid using the guest account when posting replies.
 miriam's reply was promoted to an answer.