Is _______ necessary_______ the workers wear uniforms at work?A. it, for B. this, to C. it, that
They have fun________games in the park.
English is my favorite subject,and I am good________it.
My father has a habit of jogging(慢跑)________the Jinchuan River for an hour in the morning.
You can buy some hamburgers________the kids are hungry.
Do you enjoy________books?