Re: another conditional?
Although this is 'incorrect' in terms of all the accepted ideas of tense/aspect formation, it is commonly heard in speech (especially as 'hadn't've + past participle) and, and you will see it in informal writing. In writing, it sometimes appears as 'hadn't of', a reflection of the way it's normally said.
Originally Posted by shabani
I have heard arguments that 'Had(n't have)...' is so common that it should be accepted as part of the grammar of modern English. At the moment, however, it is not accepted, so try not to use it, especially in writing. It will be marked as a mistake in examinations.
Incidentally, British speakers tend to interpret the spoken 'If I'd've' ...' as 'If I had have'. American speakers, in my experience, tend to interpret it as 'if I would have ...'.
ps. I don't agree with emsr2d2 on this. I think that it does sound natural to many speakers.
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