After Mr. and Ms. Smith spent a happy morning at the zoo with Joe, their four-year-old grandson, they stopped at a restaurant and then went into it for lunch. When the waiter passed them some menus,Mr. Smith reached into his pocket for his glasses. He was disappointed   to find that they were lost. "I know where your glasses are, Grandpa, " said the grandson. "Where?" asked Mr. Smith happily. "They are at the zoo." Joe answered. "When you took me off the train near the elephants,they fell out of your pocket." Mr.Smith was a little angry and he asked,"Joe,if you saw my glasses fall out of my shirt, why didn't you tell me?" "Well,Grandpa," said Joe, "after you put your foot on them, I didn't think you wanted them any more." The glasses fell out of the pocket when   _   .
Mr. Smith got into the zoo Mr. Smith hurried into the restaurant Joe was taken off the train near the elephants they were getting on the train