Many people like talking with the word “dog”. They love their dogs and look after them well. But dogs without owners to care for them have a different kind of life. “To lead a dog's life” tells a person has an unhappy life.
Some people say we live in a “dog-eat-dog” world. That means many people are competing for the same things, like good jobs. They say that to be successful, a person has to “work like a dog”. This means he has to work very hard. Such hard work can make people dog-tired.
Still, people say “every dog has its day”. This means that every person enjoys a successful time during his or her life. To be successful, people often have to learn new skills. Yet, some people say that “you can never teach an old dog new things”.
They believe that older people do not like to learn new things and will not change the way they do things.
We often talk about weather with the word “dog”. “The dog days of summer” are the hottest days of the year. The rain can make the weather cool. But we do not want it to rain too hard. We do not want it to “rain cats and dogs”.