The dog learns to watch (情况、状况) of the traffic and to cross the street safely . It also can understand such 指令，命令)as “sit down ” “ stand up ” “come ” “go ”, and it must know the meaning so that the owner can not get into the (危险) .
The most important part of the lesson is a four-week program in which the dog and its future owner learn to work together , , (然而)many of this kind of (残疾的) people can not get on well with dogs . Only a tenth of them find a guide dog (有用的) .
