Have been unable/ could not + verb

< Previous | Next >


Senior Member
Hi there, Can anyone please tell me whether I should use have been unable to achieve or could not achieve in the following sentence?

Here is the example :

  • In my sixty years of life I have been unable to/could not achieve what my son has achieved.
I think in the above example have been unable to is correct as the span of time is up to now.

Here is another example:

  • John, I miss those days when we used to work as a engineer in the company. Though I was a good engineer, yet my son has achieved as a engineer what I could not achieve/have been unable to do.

I think in the above context could not achieve is correct as the person is not working anymore as a engineer. His son has been working as a engineer so I used present perfect tense.
  • boozer

    Senior Member
    have been unable to achieve - suggests the speaker is probably still trying to achieve it
    could not achieve - he has stopped trying or the opportunity is now gone; if he was talking about someone else, the past tense might even suggest the person was dead
    < Previous | Next >