When you travel in Hong Kong,you must be careful of the traffic rules,because the traffic keeps to the left and it's different from that of the interior of China.Before crossing the street,you must look to the right and then to the left.If the traffic lights are red,the traffic must stop,people can go across the zebra line.If the traffic lights turn green,the traffic can go,and people mustn't cross the road. In the morning and in the evening,when people go to or come from work,the streets are very busy.The traffic is the most dangerous. When you go somewhere by bus in Hong Kong,you have to be careful,too.Always remember the traffic keeps to the left.Have a look first,or you may go the wrong way.In Hong Kong,there are a lot of big buses with two floors.You'd better sit on the second floor.From there you can watch the city very well.How interesting! When you cross the street,you must look to  _  first.
the front the right the left B and C