Mr. and Mrs Black live in a small house near London with their children. Usually Mr Black comes back from work very late. At that time, his wife and the children are sleeping. So he opens the front door of his house with his keys and comes into the house quietly. One night he comes home very late. It is 11:00 p.m. But he can't find his keys. He rings the bell . Nothing happens . He rings it again. Again nothing happens. No one can hear it. Mr. Black knocks on the bedroom window. He calls his wife's name. He shouts but his wife doesn't wake up. At last he stops and thinks for a few minutes. Then he begins to speak like a small child. "Mother," he says. "I want to go to WC." Mrs Black wakes up at once  . Then he speaks to her, and she opens the door for him. Mr. Black usually comes back  _  .
not very late before his family go to bed after his family go to bed. at about 10.p.m.