What wilt thou do? Thou wilt not murder me? Help, ho!
O, I am slain
how could you marry him mother!
come, sir, to draw toward an end with you
Hamlet enters the room to talk to his mother. He then finds out there is someone is behind the curtain, but isn't sure who it is. He then stabs the person behind the curtain because he thinks it's Claudius, but it turns out it was polonius. His fathers ghost then appears to remind him that his purpose is to avenge his death.
Hamlet verbally attacks his mother for marrying Claudius. He then tries to convince her to leave him.
Hamlet is exiting the room dragging Polonius. He is going to get rid of his body.