Mr. Brown exercises, so he is very fat.
Listen! Is Kitty in the next room? —- No, it ______ be Kitty. She has gone to Beijing.
Why did you refuse to join them in the show? —Because I don’t think the show is worth ________ part in.
You are under 18 years old, so it’s _______for you to join Trail walker.
What about listening to the English program on the radio while learning English? –Personally，___________．