tear into somebody/something phrasal verb ( see also ↑ tear )
1 . to attack someone by hitting them very hard:
The two boys tore into each other.
2 . to criticize someone very strongly and angrily:
From time to time she would really tear into her staff.
3 . to start doing something quickly, with a lot of energy:
I was amazed at the way she tore into her work.