1

Suppose we have the following example situation:

Martin is obliged to paint the walls red, but he has painted them green. I'm disappointed. I say:

  1. Oh, Come on! You can't have painted the walls green. You must have painted them red.
  2. Oh, Come on! You can't have painted the walls green. You should have painted them red.
  3. Oh, Come on! You shouldn't have painted the walls green. You must have painted them red.
  4. Oh, Come on! You shouldn't have painted the walls green. You should have painted them red.

Can we use can't / shouldn't have (done) for expressing disappointment and must / should have (done) for unfulfilled obligation in the past?

Which ones of the above would be the correct ways of expression?

Improve this question
6
  • 1
    It depends on the strength of Lucy's expectation that they would be home and the need (such as if it was some kind of emergency). 1. has more urgency than 2.
    – user3169
    Oct 1, 2017 at 0:04
  • @user3169 So if I understand you well, they all are correct and quite natural ways of expressing something that is not what we expect. And the only difference is the meaning difference which is quite subtle and there are many cases when all these sayings might be used more or less interchangeably. Am I right?
    – Karolini
    Oct 1, 2017 at 10:42
  • 4. would be OK is there was an expectation that they might have gone somewhere else. But don't use 3. because you wouldn't follow such an expectation with the firm belief that they are there.
    – user3169
    Oct 1, 2017 at 16:34
  • @user3169 I have rewritten my post for better reflection of question's essence. Would you have a look at it?
    – Karolini
    Oct 3, 2017 at 10:28
  • 1
    This doesn't make logical sense in English. You can't say "You can't have painted the walls green." because it is already done. This would need to be "How could you have painted the walls green?" - "You should have painted them red."
    – user3169
    Oct 3, 2017 at 20:38

1 Answer 1

Reset to default
1

I would not use You can't have painted the walls green here; it would imply that it is impossible (rather than undesired) that the action occurred, as in doubting a claim that something has occurred. Example: "You can't have heard that, because you were too far away."

"You shouldn't have" is an expression of dissatisfaction/disappointment. If you want a stronger form, you can use "You were not supposed to pain the wall green."

In the second sentence, "you should have" would be perceived as a suggestion; "you were supposed to", or "you were told to", would be a correction.

"You must have" is an assertion that something occurred; it is the opposite of "You can't have." Example: "You must have been scared, because you were looking so pale."

Improve this answer
3
  • 1
    ``Oh no, you cant have painted the walls green" sounds perfectly normal to me. The speaker is both surprised and horrified, and expresses this through hyperbole, asserting that an event is impossible when it was merely improbable
    – Philip Roe
    Oct 4, 2017 at 3:11
  • @PhilipRoe If I understand you well, the meaning of this hyperbole is more like "Oh no, you certainly haven't painted the walls green" than "Oh no, It can't be (or I can't believe) that you have painted the walls green". Am I correct?
    – Karolini
    Oct 4, 2017 at 11:19
  • 1
    @Karolini No, what I intended was the second. Its one of those phrases that you would understand if you came across it for the first time when it was spoken. ``Oh no you cant have painted the walls green! I took such care explain to you why they must be red! I even showed you the exact shade that I wanted! Green will be terrible! The red paint was on sale!" There are so many reasons against green that I cannot believe you did that stupid thing. If you come across it for the first time in writing, it is hard to imagine the strong reaction that is implied by the use of this phrase.
    – Philip Roe
    Oct 5, 2017 at 18:55

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .