Because of the interrogations
We use
personal pronouns in place of noun phrases. We often use them to refer
back to people and things that we have already identified (underlined):
<span>Peter complained to the chef about the meal. She wasn’t very helpful so he spoke to the manager.</span> (she = the chef, he = Peter)
<span>A:<span>Where’s the knife? I can’t find</span> it.B:It’s in the drawer. (it = the knife)</span>
Personal pronouns show person and number. He, she, him and her show gender. They have different subject and object forms (except you, it and one which have only one form):