During working hours, the traffic is very heavy on most city streets; therefore you should be aware of the traffic laws. It is against the law in many cities to cross the street at any place except at the comer. You should not cross the street unless there is a green light facing in the direction you plan to cross. Obeying traffic signals is especially important if you come from a left-hand drive country. Remember to look both ways for automobiles(汽车) when you cross the street.