A dog has a life expectancy of more than 10 years. The period between six months to one and a half years are a dog's adolescence, and it is also the best time for training. After this time a dog's personality becomes set and it is difficult to train.
一隻狗大約有十多年的壽命，六個月到一年半是狗的「青少年期」，也是最佳訓練時期，過了這個時候，狗性已成，就很難訓練了。