what is p1 p2 p3 and p4 mean?

10 answers

I would assume "page 1, page 2," etc. I do not have the context you are looking at, though, so it's hard to tell from here.
p1 sn v
These are Shurley English abbreviations.

pattern 1, subject, noun verb

http://www.google.com/#q=shurley+abbreviations
i do not understand how to get the answe
answer
Study your English materials. Study the link I posted.

Besides, I gave you the answer.
This site explains some of the vocabulary, including sentence patterns.

http://images.pcmac.org/SiSFiles/Schools/AL/BaldwinCounty/JLarryNewton/Uploads/DocumentsCategories/Documents/Shurley%20Grammar-%20Quick%20Guide.pdf
so like this ?
the weathered old raft was drifting downstream by itself.
it is p1?
Yes, it's sn v. It's pattern 1.