3

Here are two examples from Murphy grammar textbook:

1)"I didn't see you at Michael's party last week - No, I had to work that night, so I couldn't come."

2)"I think I saw you at Michael's party last week- No, you couldn't have seen me. I didn't go to the party."

My question is:

Why in the first example is there no "couldn't have come" instead of "couldn't come" despite the past context ("...last week", "I HAD to work...")?

John Lawler
  • 107,887
kacherese
  • 295
  • @FumbleFingers It's not a duplicate. Your reference is a complaint. The above example is a conclusion. – Cathy Gartaganis Apr 19 '16 at 18:16
  • 1
    @Cathy Gartaganis: Complaint, conclusion - doesn't make any difference to the syntactic issues here. Which I think are adequately covered by this answer on the original – FumbleFingers Apr 19 '16 at 18:29
  • @FumbleFingers The EFL learner asking the question is not aware of the different functions of couldn't + have + past participle, and needs guidance. An EFL learner will not be able to infer from your reference to a complaint that the same construction can also be used for an impossibility. I have 25 years of experience teaching EFL learners. – Cathy Gartaganis Apr 19 '16 at 18:54
  • @Cathy Gartaganis: The ELF learner should be asking questions on English Language Learners, not ELU. – FumbleFingers Apr 20 '16 at 11:40
  • @FumbleFingers It's not clear whether kacherese is a native speaker or not. I simply provided an answer that covers all levels. Many native speakers have gaps in their knowledge as well. – Cathy Gartaganis Apr 20 '16 at 15:56
  • Well in fact I looked through that topic about Harry Potter and wasn't able to find anything useful and clarifying. By the way, I'm not native speaker, but I considered that my question rather relates to usage and semantics. – kacherese Apr 21 '16 at 08:01

2 Answers2

1

I couldn't come = I was unable to come

You couldn't have seen me = It's not possible you saw me (since I wasn't there).

He couldn't have killed her. He was with me all night.

"A firework couldn’t have done all that damage."

http://dictionary.cambridge.org/grammar/british-grammar/could

A sentence with 'couldn't have + p.p.' proves a previously made statement wrong. A sentence with 'couldn't + inf.' simply states a fact; it isn't proving anything wrong. The construction 'couldn't have +p.p.' cannot stand alone. It needs to be preceded by a false statement, whereupon the construction is used, followed by proof, to prove the statement is wrong.

For example: false statement : This little boy wrote the essay in front of you. Response: He couldn't have written it; he hasn't even learned the alphabet yet./ He couldn't write his homework today because he broke his wrist.

In your example, you state a fact; you don't prove anything wrong. You say 'I couldn't come to the party; I had to work.

It was not possible = I was unable = I couldn't come , but I couldn't have come = it's impossible for you to conclude that I was present, for example, You say you saw me at the party, but I couldn't have been at the party since I was at home. It's awkward to say: I couldn't have come to the party. - though it has the same meaning as I couldn't have been at the party - You couldn't have seen me there. (not I had another obligation - that's I couldn't come)

Cathy Gartaganis
  • 2,448
  • 12
  • 10
  • Why can't I say then: "I had to work that night, so I couldn't have come"? Wouldn't it mean "it was not possible for me to come"? – kacherese Apr 19 '16 at 18:51
  • 1
    It was not possible = I was unable = I couldn't come , but I couldn't have come = it's impossible for you to conclude that I was present, for example, You say you saw me at the party, but I couldn't have been at the party since I was at home. It's awkward to say: I couldn't have come to the party. - though it has the same meaning as I couldn't have been at the party - You couldn't have seen me there. (not I had another obligation - that's I couldn't come) – Cathy Gartaganis Apr 19 '16 at 18:58
  • If I used "I couldn't have come" then according to Murphy, that would be a mistake. Why is that so? That's what I'm trying to find out. – kacherese Apr 19 '16 at 19:01
  • 1
    @kacherese A sentence with 'couldn't have + p.p.' proves a previously made statement wrong. A sentence with 'couldn't + inf.' simply states a fact; it isn't proving anything wrong. The construction 'couldn't have +p.p.' cannot stand alone. It needs to be preceded by a false statement, whereupon the construction is used, followed by proof, to prove the statement is wrong. For example: false statement : This little boy wrote the essay in front of you. Response: He couldn't have written it; he hasn't even learned the alphabet yet./ He couldn't write his homework today because he broke his wrist. – Cathy Gartaganis Apr 19 '16 at 19:17
  • 1
    @kacherese In your example, you state a fact; you don't prove anything wrong. You say 'I couldn't come to the party; I had to work.' – Cathy Gartaganis Apr 19 '16 at 19:19
0

Big thanks to Cathy Gartaganis for explaining semantics of the "couldn't have" construction.

Here's the answer:

"A sentence with 'couldn't have + p.p.' proves a previously made statement wrong. A sentence with 'couldn't + inf.' simply states a fact; it isn't proving anything wrong. The construction 'couldn't have +p.p.' cannot stand alone. It needs to be preceded by a false statement, whereupon the construction is used, followed by proof, to prove the statement is wrong."

kacherese
  • 295