Subject in Preposition

[yellowho]

Can someone clarify this:

1) I read in multiple sources that the subject of a sentence cannot be within a preposition phrase. Can someone confirm/deny this?

2) Here, "galaxies" is not the subject but it is the antecedent to "them". Is this grammatical?

3) Does this sentence even make any sense? It feels like something is missing with "astronomers who keep track of the number have found approx. 5 million." Shouldn't it be "that number"?

[hja379]

Can someone clarify this:

1) I read in multiple sources that the subject of a sentence cannot be within a preposition phrase. Can someone confirm/deny this?

2) Here, "galaxies" is not the subject but it is the antecedent to "them". Is this grammatical?

3) Does this sentence even make any sense? It feels like something is missing with "astronomers who keep track of the number have found approx. 5 million." Shouldn't it be "that number"?

That is correct. The subject cannot be in the prepositional phrase. But in the sentence above, subj is 'the number' which is not preceded by the preposition. The antecedent 'it' is confusing at best, as it is not clear whether it refers to the 'number' or the 'earth'. Hope this helps.

[Jim@Grockit]

Also "keep a track" probably ought to be "keep track." What's the source?

And yes, "them" can refer back to "galaxies" -- the key with "them" is making sure it only has one plural noun that could be the referent.