Nuances between Modals

Question

Dear teachers,

- What is the difference in meaning between all these sentences ? Are they all correct ?

1a) My friend MAY BE ill. = Present; There is a strong possibility ?
b) My friend MIGHT BE ill. = Conditional; There is a weaker possibility ?
c) My friend MIGHT HAVE BEEN ill. = Past, a weak possibility ?

d) She MIGHT not HAVE SEEN him, if he didn’t come up to her. = Past: she saw him.

2a) My friend CAN be ill. = incorrect ? / = Possibility ?
(If correct what's the difference between "CAN BE ill" and "MAY BE ill" ?)

b) My friend COULD BE ill. = Past possibility /
= Conditional: the possibility is stronger than with might ?

c) My friend COULD HAVE BEEN ill. = Past possibility ? difference with b ?

d) She COULD HAVE SEEN him. = past possiblity ?

3a) My friend CAN’T BE ill. = It’s impossible that she is ill.
b) My friend COULDN’T BE ill. = Present: is less certain than with 'can’t'? /
= Past impossibility ?

c) My friend COULDN'T HAVE BEEN ill. = Past impossibility ? difference with b) ?

d) She couldn’t have seen him = It is impossible that she saw him?

4a) The phone is ringing. It CAN BE Betty. (correct ? expresses possibility ?)
b) The phone is ringing. It MAY BE Betty. (correct ? difference with a) ?)
c) The phone is ringing. It MUST BE Betty. (= certain deduction ?)
d) The phone is ringing. It HAS TO BE Betty. (difference with c) ?)
e) The phone is ringing. It WILL BE Betty. = certain deduction about the present / prediction
difference with c) and d) ?

5a) That will be Roland. I can hear him at the door.

b) “Oh, that will be John. He said he would drop by this afternoon."
(direct speech = certain deduction / prediction)

c) That would be John, Mary thought. He had said that he would probably drop by.
(same thing “present deduction with a high degree of certainty” but in indirect speech ?)

d) That will have been Roland… (what can I add here ?) = (correct ? / possible sentence ?)

- What’s the difference between “would” and “will have been”?)

I know that this is quite long but I would be very grateful if you could answer all of my questions. In different posts if you like.

Best regards,
Hela

MrPedantic · Accepted Answer

Hello Hela

Here's a note on 'will have' (5d), to start with.

A: Who said that?
B: That will have been Roland.

When B says 'that will have been Roland', the 'saying' itself is a finished action, but the identity of the speaker is not yet certain. It's a possibility that will only be confirmed in the future, which is why we use 'will':

MissC: Someone said you were seen with MrP last night.
MissA: That's outrageous. Who said that?
MissB: That will have been Roland. He's always making snide comments about you...

{Later, in the pub.}

MissA: I've got a bone to pick with you, Roland. Have you been spreading vicious rumours about me again?
Roland: {innocent} I don't know what you're talking about...
MissA: Oh yes you do. What have you been saying about me and MrP?
Roland: Nothing at all! Honestly!
MissA: Are you sure?
Roland: Absolutely.
MissA: Well, I wonder who it was, then.
Roland: What did they say?
MissA: They said I was seen with MrP last night.
Roland: With MrP? How bizarre....Well, if you want my opinion, that will have been MissB.
MissA: MissB! But she said it was you!

In other words, 'That will have been Roland' means:

'That will (turn out to) have been Roland.'

Cf 'will' (5a and b):

{doorbell rings}
'That will be MrP.'

The doorbell 'rang' a moment ago, and MrP is standing at the door; but the identity of the person who rang the doorbell is still uncertain. So we use the future: it means 'that will (turn out to) be MrP'.

'Would be' can be a reported speech version:

1. When the doorbell rang, Mary said that it would be MrP.

or a more 'remote' version:

2. 'It looks like there are two girls at the door with MrP.'
'Oh, that would be MissA and MissB.'

MrP

CalifJim · Answer

Hi, Hela,

1. "may", "might", and "could" (but NOT "can") are used to show "it is possible that ... something IS or will be so"

My friend [may / might / could] be ill. (It is possible that my friend is ill.)

Some people try to determine which of these expresses a stronger possibility, and which a weaker one. I personally don't think it's worth the trouble to split hairs over it. Note that "may" is sometimes ambiguous between possibility and permission, whereas the other two are not. For this reason, I think it's important to master "might" and "could" first.

2. "may have", "might have", and "could have" are used to show "it is possible that ... something WAS or would be so".

My friend [may have / might have / could have] been ill. (It is possible that my friend was ill.)

3. In addition to the meaning in 1b, there is another context where "might have" or "could have", but NOT "may have") can be used. If you already know the results of some action, you can speculate on how that action [might have / could have] happened instead.

I can't believe you climbed to the top of that tree. You [might have / could have] fallen and broken your neck!

4. Another use of "might have" and "could have" is to give a mild reproach.

You know, you [might have / could have] forewarned me that you were going to bring the boss home for dinner.
___________

1a) My friend MAY BE ill. = Present; There is a strong possibility ? - see above
b) My friend MIGHT BE ill. = Conditional; There is a weaker possibility ? -see above
c) My friend MIGHT HAVE BEEN ill. = Past, a weak possibility ? -see above (It is possible that my friend was ill.)

d) She MIGHT not HAVE SEEN him, if he didn’t come up to her. = Past: she saw him.
(This is the counterfactual use. We know already that she did see him.)

2a) My friend CAN be ill. = incorrect ? / = Possibility ? - NO
(If correct what's the difference between "CAN BE ill" and "MAY BE ill" ?) "can be ill" is not used.

b) My friend COULD BE ill. = Past possibility / - NO. Present possibility - see above. (It is possible that my friend is ill.)
= Conditional: the possibility is stronger than with might ? Mmmm. Hard to say. Not really.

c) My friend COULD HAVE BEEN ill. = Past possibility ? difference with b ? (It is possible that my friend was ill.)

d) She COULD HAVE SEEN him. = past possiblity ? (It is possible that she saw him. / She had the ability/opportunity to see him) (At least these two meanings here.)

3a) My friend CAN’T BE ill. = It’s impossible that she is ill. YES. It is not possible that she is ill.
b) My friend COULDN’T BE ill. = Present: is less certain than with 'can’t'? /
= Past impossibility ? NO. Present impossibility. It is not possible that she is ill.

c) My friend COULDN'T HAVE BEEN ill. = Past impossibility ? difference with b) ? (It is not possible that my friend was ill.

d) She couldn’t have seen him = It is impossible that she saw him? YES (It is not possible that she saw him. / It must be that she did not see him.)

4a) The phone is ringing. It CAN BE Betty. (correct ? expresses possibility ?) Not used. But the negative is used: It can't be Betty. (It is not possible that it is Betty.)
b) The phone is ringing. It MAY BE Betty. (correct ? difference with a) ?) OK It is possible that it is Betty.
c) The phone is ringing. It MUST BE Betty. (= certain deduction ?) OK The only logical conclusion is that it is Betty.
d) The phone is ringing. It HAS TO BE Betty. (difference with c) ?) Meaning is same as c). Somewhat awkward to my ear. It seems extremely informal to me, or desperate, or both!
e) The phone is ringing. It WILL BE Betty. = certain deduction about the present / prediction
difference with c) and d) ? (It probably is Betty. - Extremely rare in American English.)

Mr. P. handled 5 already, so I won't repeat unless you have additional specific questions, OK?

Jim

Hela · Answer

To the webmasters,

It seems that I received other messages from Mr Pedantic and JTT but I can't read them on this page. Why's that ?

Would you please them back to me?

Many thanks.
Hela

Hela · Answer

Dear JTT,

I went through your detailed comments, at least those I received, but I need to read them more attentively. I didn't find anything though about the following sentences :

4c) The phone is ringing. It MUST BE Betty. (= certain deduction ?)
d) The phone is ringing. It HAS TO BE Betty. (difference with c) ?)
e) The phone is ringing. It WILL BE Betty. = certain deduction about the present / prediction /
difference with c) and d) ?

What's your view about them ?

Many thanks,
hela

Pieanne · Answer

May I try ?
4c) it must be Betty (I'm expecting her call)
d) it has to be Betty (Many people were supposed to call me now, and she's the only one who hasn't called yet)
e) it will be Betty (she always calls at this time of the day)

MrPedantic · Answer

Hello Hela

I think JT must have deleted his comments after my second post yesterday. (Pity. They looked quite interesting. But perhaps he was dissatisfied with them in some way.)

My second post is now incorporated into my earlier post on this thread (I redid my two posts, once the earlier ones were gone, as otherwise they wouldn't have made sense).

Sorry about the confusion!

Bye for now,
MrP

MrPedantic · Answer

Those look fine to me, Pieanne.

I'm interested in CJ's 'desperate' has-to-be: that happens in BrE too:

1. 'That has to be Betty!' – when you've been waiting for Betty to call all day; maybe you're desperate for some piece of information she's going to give you.

'That'll be/It'll be...' is quite a common form in BrE, e.g.

2. 'Who's printing out a 50-page document?'
'Oh, sorry...that'll¹ be me...'
'But I need this printer now!'
'Sorry...it'll² be finished soon...'

(That'll¹ and It'll² have quite different functions in this dialogue.)

MrP

CalifJim · Answer

Mr. P.,

I had a feeling someone would draw attention to that word "desperate"! Yes, your example is the sort of thing I was referring to! "must be" is pretty neutral in comparison.

As for 2, you're quite right, the "that'll" (in that dialog) is not American English. The "it'll", on the other hand, is. In AmE the response is: "Sorry! I am!" or, more rarely, "Sorry! That would be me!".

CJ

Hela · Answer

Dear Moderators,

You seemed not accept CAN / COULD as an expression of possibility but what do you think of the following ? Are my statements and examples true ?

CAN = POSSIBILITY

1) CAN in the PASSIVE expresses possibility:

a) Arsenal can beat (is able to beat) Nottingham Forest.
b) Nottingham Forest can be beaten by Arsenal. (it’s possible for Arsenal to beat N.F.)

2) CAN: expresses PHYSICAL, FACTUAL possibility. ("en fait")

a) If it is raining tomorrow, the sports CAN take place indoors.

b) Jane CAN / COULD / MAY / MIGHT BE at home.

but if I say:

c) "Jane CAN / COULD WORK at home." (= ABILITY?) would it be different from :
d) "Jane CAN /COULD BE WORKING at home." (= POSSIBILITY ?)
e) "Jane MAY / MIGHT WORK at home".

3) CAN + Bare infinitive: is used to express:

A/ a GENERAL POSSIBILITY. It means it is possible (? may)
a) You CAN ski on the hills. (there is enough snow)
b) CAN you get to the top of the mountains in one day / by cable car ?
(= it’s possible for you to… )

B/ an OCCASIONAL POSSIBILITY in the affirmative form.
a) He CAN be silly at times.
b) Even doctors CAN MAKE mistakes (it’s possible sometimes)
c) Measles / Driving at night CAN BE quite dangerous.

4) COULD + Bare infinitive: is used to express a DOUBTFUL possibility, a guess (?) in the PRESENT time.

ex: What kind of tree is this? It COULD BE a maple tree.
(I guess it is possible for this to be a maple tree)

5) COULD + Perfect infinitive: expresses

A/ an UNREALIZED PAST opportunity.

ex: She COULD HAVE finished today, but her typewriter broke down.
(It was quite possible for her to finish if her typewriter hadn’t broken down = she didn’t finish typing)

B/ a past possibility where we don’t know whether the action was performed or not. It is similar to MAY and MIGHT.

a) The money has disappeared! Who COULD HAVE taken it ?
b) Tom COULD HAVE (taken it); he was here alone yesterday.

c) He COULD HAVE have sent a message =
- He did not send it. / - We don’t know if he sent it.

6) CAN’T + Bare Infinitive: denotes an impossibility in the present or a near certainty.

a) He CAN’T do that to me. (negative deduction based on present evidence)
b) He CAN’T be at home.

7) COULDN’T + Bare Inifinitive: is more tentative, less definite than CAN’T.

ex: He COULDN’T be at home. (the impossibility is less certain)

8) CANNOT / COULD NOT + Perfect infinitive: expresses an impossibility in :

a) He CAN’T HAVE done that. (negative deduction based on past evidence)
b) That crime CAN’T / COULDN'T HAVE BEEN committed by my brother; he was abroad with his wife at the time. (It’s impossible that he could have)

Thank you very much for your patience.
Kind regards,
Hela

CalifJim · Answer

You seemed not accept CAN / COULD as an expression of possibility but what do you think of the following ? Are my statements and examples true ?

[Actually, "could" is quite usable as "It is possible that ...": William could be waiting for us right now. (It is possible that William is waiting for us right now.) "can" is not used in this context, however.]

CAN = POSSIBILITY

1) CAN in the PASSIVE expresses possibility:

a) Arsenal can beat (is able to beat) Nottingham Forest.
b) Nottingham Forest can be beaten by Arsenal. (it’s possible for Arsenal to beat N.F.) [Yes.]

2) CAN: expresses PHYSICAL, FACTUAL possibility. ("en fait")

a) If it is raining tomorrow, the sports CAN take place indoors. [Yes.]

b) Jane CAN / COULD / MAY / MIGHT BE at home. [No. All but "can" OK here. The version with "can" is highly unusual; however, "Jane can stay at home" is normal. It means "Jane has the ability to stay at home" or "Jane is permitted to stay at home" or "Jane has the option of staying at home (if she wishes)".]

but if I say:

c) "Jane CAN / COULD WORK at home." (= ABILITY?) would it be different from :
d) "Jane CAN /COULD BE WORKING at home." (= POSSIBILITY ?) [Yes, these are different. In the sense of possibility, "can" is not used. It's "may", "might", or "could".]
e) "Jane MAY / MIGHT WORK at home". [With "may" it means "It is possible that Jane works at home" or "Jane is permitted to work at home". With "might" it means "It is possible that Jane works at home".]

3) CAN + Bare infinitive: is used to express:

A/ a GENERAL POSSIBILITY. It means it is possible (? may) [Not sure what you mean here, since "may" = "it is possible that ..." in one reading of "may". The difference, in my opinion, is that "can" is 'subject-oriented'. Whereas "may" means "it is possible that" in one reading, "can" means "it is possible for 'the subject' to ... Also, "may" in this reading focuses on the logical properties of the proposition; "can" focuses on matters of fact in the real world, so to speak.]
a) You CAN ski on the hills. (there is enough snow) [Yes. Conditions in the real world make it possible.]
b) CAN you get to the top of the mountains in one day / by cable car ?
(= it’s possible for you to… ) [Yes.]

B/ an OCCASIONAL POSSIBILITY in the affirmative form.
a) He CAN be silly at times. [Yes.]
b) Even doctors CAN MAKE mistakes (it’s possible sometimes) [Yes.]
c) Measles / Driving at night CAN BE quite dangerous. [Yes.]

4) COULD + Bare infinitive: is used to express a DOUBTFUL possibility, a guess (?) in the PRESENT time.

ex: What kind of tree is this? It COULD BE a maple tree. [Yes. It is possible that it is a maple tree. / It would be possible that it is a maple tree.]
(I guess it is possible for this to be a maple tree)

5) COULD + Perfect infinitive: expresses

A/ an UNREALIZED PAST opportunity.

ex: She COULD HAVE finished today, but her typewriter broke down.
(It was quite possible for her to finish if her typewriter hadn’t broken down = she didn’t finish typing) [Exactly.]

B/ a past possibility where we don’t know whether the action was performed or not. It is similar to MAY and MIGHT.

a) The money has disappeared! Who COULD HAVE taken it ? [Yes. Who had an opportunity to take it?]
b) Tom COULD HAVE (taken it); he was here alone yesterday. [Yes. Tom had an opportunity to take it.]

c) He COULD HAVE have sent a message =
- He did not send it. / - We don’t know if he sent it. [Yes. Two different interpretations of the sentence. 1. He had an opportunity to send a message; we know he did not follow through on that opportunity; we know he did not send it. 2. It is possible that he sent a message; we don't know.]

6) CAN’T + Bare Infinitive: denotes an impossibility in the present or a near certainty.

a) He CAN’T do that to me. (negative deduction based on present evidence) [Besides the literal meaning, there is the idiomatic reading "I won't let him do that to me", "I won't tolerate him doing that to me", "Just let him try to do that and I'll get revenge".
b) He CAN’T be at home. [It is not possible that he is at home. Also expressed (less often, perhaps) as "He must not be at home" ("One can only conclude that he is not at home.")]

7) COULDN’T + Bare Inifinitive: is more tentative, less definite than CAN’T.

ex: He COULDN’T be at home. (the impossibility is less certain) [Perhaps less certain, yes.]

8) CANNOT / COULD NOT + Perfect infinitive: expresses an impossibility in :

a) He CAN’T HAVE done that. (negative deduction based on past evidence) [Yes. It is not possible that he did that / that he has done that.]
b) That crime CAN’T / COULDN'T HAVE BEEN committed by my brother; he was abroad with his wife at the time. (It’s impossible that he could have) [Yes. Same idea as in 8a).]

CJ

Nuances between Modals

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