Sam is going to the zoo with his classmates this afternoon. He will go by bus and get there at 3 o'clock. The bus stop is near his home. He's going to get on the bus at half past two. Then he can get there on time (按时;准时). There are lots of animals at the zoo. They're going to visit the lions, the elephants, the bears and the tigers. And they're going to go home at half past six.