Which words make up the prepositional phrase in this sentence? along the back fence shuffled what looked like a large gray cat.

Along the back fence is the prepositional phrase because prep phrases can't have verbs; only clauses. Prep phrases have to include a preposition, noun, and usually an article (a, the, an).

Here's a song so you can remember prep phrases better: https://www.youtube.com/watch?v=yfExXGMX2JM

There is nothing inherently wrong with being gay. speaking generally, opposition to gays are usually judged on people's moral basis whether it be religion, experience or other factors. to conclude, there is no objective answer to this question only subjective ones that rely on people's idea of what is right and wrong.