单项选择题A．A chemistry class.B．A biology class.C．A mathematics class.D．A physics class.

单项选择题A．At a railway station.B．At a bus center.C．In the countryside.D．In a coastal town.

单项选择题A．Money.B．Ships and planes.C．Florida.D．Trains and cars.

单项选择题A．A two-bedroom apartment.B．A sofa.C．A chair.D．A roommat

单项选择题A．To warn of dangers.B．To explain traffic regulations.C．To wake up drivers who are falling asleep.D．To give directions.