If you say "This is some stuff I hate to put up with," and someone complains about your sentence ending in a preposition, I think the correct rephrasing is "This is some stuff I hate to put up with, you asshole." But here are some more serious answers:
"Stuff I hate to put up with" does not end with a preposition - "put up with" is functioning as a compound verb here. It's like saying "Popsicles I hate to lick." Anyone who hassles anyone about this should refer to paragraph one.
"I don't want to exercise, but I have to" becomes (if one wants to follow this arbitrary rule, which, to reiterate, one needn't) "I don't want to exercise, but I have to exercise," or alternately, "Though I have to, I don't want to exercise."
It is specifically to demonstrate the absurdity of the rule that I wish to phrase more nearly (and technically correctly) like my last example there, serving to obscure rather than clarify communication.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
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