单选题
Look at the car. It"s Mr. Black"s car. It doesn"t work now. Mr. Black is under it. He is mending it. Mrs. Black is near the car. She is helping Mr. Black. The girl in the car is Kate, Mr. Black"s daughter. Who is the boy in the car? He is Jim, Kate"s brother. It"s Saturday today. They don"t work. They want to go to the park. They all look worried.