I've been told that compound contractions like couldn't've and I'd've are proper grammar. Are they?
4They're incredibly common in spoken language, but people don't generally write them down.– Peter ShorApr 30, 2013 at 15:57
5Depends on whatcha mean by proper grammar. Contractions of any kind are rarely allowed in formal academic prose (eg, in PhD dissertations & published articles in academic journals), but in informal writing (between friends, in chat rooms, text messages, & forums like this) they're common enough. I use 'em all the time. Most people don't, as Peter Shor says. I'd've written a few more in this comment, but I didn't see a need for any. I use "couldn't've" and "wouldn't've" all the time here: saves character spaces in comment boxes. If readers understand 'em, they're fine. If not, they're bad.– user21497Apr 30, 2013 at 16:04
1Grammatically they can be correct, but as the above gents stated, from a style standpoint, they are not used in formal writing.– Kristina LopezApr 30, 2013 at 17:57
3It seems like a petty nuisance to use yet more apostrophe's in order to document (poorly) what people actually say. Myself, I just write couldna. Saves time, and anybody who'd object is somebody I'd sooner avoid anyway. In any case, punctuation and spelling are not grammar.– John LawlerApr 30, 2013 at 18:37
2Yes, that's not a grammatical point. The plural ends in /iz/, as always. How one chooses to represent this is not a matter of grammar, but of technology.– John LawlerApr 30, 2013 at 19:30
Internationally, compound contractions are not regarded as correct grammar. Even simple contractions should be avoided, if possible, in a formal or academic context.
High school English teaching in my country, 'English for foreigners' courses, as well as the exam boards which provide English proficiency certifications (Cambridge ESOL) mark them as incorrect. I'm talking mainly about British English here, as it is the more common form of 'language import' in Europe. I don't know about TOEFL or other AE testing institutions.
In the UK (at least in southern England) however, you might find the issue to be a bit more complicated. Double contractions are very common in spoken language, and I have occasionally encountered them on flyers, posters or informal letters. On the other hand, exam boards like OCR and AQA won't accept them as correct, when doing A-levels exams.
So you could say as a thumb rule you should avoid them if you are writing prose in a formal setting. If you are writing for yourself, to friends or family, you might use it. You can also use it within the quotation marks, when writing direct speech of a common person.