1.
If you fence something in , you surround it completely with a fence.
He plans to fence in about 100 acres of his ranch five miles north of town.
PHRASAL VERB : V P n
2.
If you are fenced in by someone or something, they are so close to you that you are unable to move or leave.
She was basically fenced in by what the military wanted to do...
He put his hand on the post behind her so that he had her fenced in and could look down on her.
PHRASAL VERB : usu passive , be V-ed P , V-ed P