prepositions - "Bring up the subject" vs "bring the subject up"

Example:

I stared at my brown sneakers, deciding whether to bring up the subject.

I stared at my brown sneakers, deciding whether to bring the subject up.

What's the different between the two? Are both grammatical? Which one is more common?

Answer

With a verb + preposition combination like this one (sometimes called a separable phrasal verb), we can choose to put the Object either before or after the preposition:

• Take the rubbish out.


• Take out the rubbish.

When the Object is a pronoun it must go before the preposition and cannot go afterwards:

• Take it out.


• *Take out it. (ungrammatical)

Notice here that pronouns are very short, usually only one syllable.

And if the Object is very long, native speakers prefer to put it after the preposition. It can sound very bad if we put a long Object before the preposition:

• I'm taking the rubbish you left lying around on the floor yesterday afternoon out. (awkward - long Object in the middle)


• I'm taking out the rubbish you left lying around on the floor yesterday afternoon. (good - long Object after the preposition).

The Original Poster's question

The Object in the Original Posters question isn't very long. It's only three syllables. It isn't a pronoun either We can choose therefore whether to put it before or after the pronoun. There might be other factors that make us more likely to choose one or the other. For example, whether the subject represents old or new information. Or, maybe more importantly whether one choice is more idiomatic than the other.

In my opinion bring up the subject is more idiomatic than bring the subject up although both are entirely grammatical. Here's an Ngram comparing the two, which seems to back up my idea. Blue shows bring up the subject and red shows bring the subject up. It looks as if bring up the subject might be more idiomatic. However, remember that it's only an Ngram, so there might be other reasons for one being more common than the other:

Edit note: Just to illustrate that native speakers' intuitions may be different, see Racheet's helpful comments below!