Betty:Good morning,Alan!You look pale,are you all right?
Alan:I'm OK,but I saw an accident.A boy was riding his bike and listening to music on the road.
Daming:That's very dangerous.
Alan:I was waiting to cross the road.While the lights were changing to red,a car suddenly appeared round the comer.It wasn't going fast,but it didn't stop.
Lingling:Did the boy stop?
Alan:No.And the driver was talking on his mobile phone.
Betty:So,did the car hit the boy?
Alan:No,I'm glad to say.The car stopped just in time,but the boy fell off his bike and hurt his knee.
Tony:That's too bad.
Alan:So when you're on your bike,think about the risk of an accident!Pay attention,stop at the red lights and. . .what else?