Ending a sentence with a preposition is considered a bit of a faux pas among some of the more sophisticated circles, yet most English speakers do it on a regular basis. So is it really that bad? Is it even wrong at all?
The primary argument against using prepositions at the end of a sentence (or more accurately, a clause) is that prepositions by definition are ‘positioned before’ a noun phrase, while the argument for laxity on that rule comes from the idea that some sentences are just terribly awkward if you’re forced to place prepositions before noun phrases.
You can see how bizarre that sounds. But there is a solution that may satisfy both parties.
Perhaps the problem is that ‘prepositions’ is almost misnomer. Sometimes a preposition more connected with the verb it follows than with the noun it precedes. Many ESL books teach Phrasal Verbs (or Multi-Word Verbs, depending on the publisher), in which a base verb is followed by a preposition. Examples include ‘deal with’, ‘count on’, or ‘take after’. The two words are treated as one, almost like a compound-verb, and sometimes their combination creates a very different meaning from the base verb by itself.
To address Churchill’s quote, ‘put up’, or even ‘put up with’, is considered a phrasal verb.
So it boils down to [notice that phrasal verb] whether a preposition is more importantly linked to a noun or to a verb in any given context. While some might argue that ‘up’ should come before either ‘thing’ or ‘which’ (which references ‘thing’), I’d argue that you shouldn’t separate it from ‘put’. The more distance you put between those two words (not to mention switching the order), the less clear their connection is. That makes it harder to tell it’s a phrasal verb, which then changes the inferred meaning of the sentence.
So the next time the argument over prepositions comes to you, just think about which is more important: that the preposition comes before the noun, or that the preposition comes after the verb.