School was over. Usually David's mother would take him home from school but today she was not here. David decided to go home alone foot, and it took him about half  hour. When he got home, he couldn't get in he did not bring his keys. He knocked on the door, but no one answered. David thought his mother (be) in the toilet, so he waited patiently for her. After a few  (minute), David knocked again, but still no one answered. "What is happening? Is there anything wrong with my mother?" he thought to (he) and got worried. Just at that moment, he heard the (friend) voice of his neighbour, John. David told him that no one was at home, and John asked him (stay) in his house. Two hours later, when David's mother got back, he (play) games with John.  happy he was to see his mother！