PHRASES
Tests (proofs) for structure: a
1-replacement /substitution
It's oftion possible to replace a constituent with a single word having THE SAME MEANING as that constituent
example:
I was reading a book
I was reading it
BOOk
IT
the meaning of the sentence doesn't change
SO (a book) is a phrase
2- deletion
3- movment
if some part of a sentence can be moved to other place, it is a constituent /phrase
I bought new clothe yesterday
, Yesterday, I bought new clothe
and there are other tests, but these above are the basic