Dogs can do a lot of work for man. They play with us. They hunt with us. They keep door for us. But long ago, dogs all over the world were wild. Dogs can date back to the Stone Age. All dogs have the same ancestor. It is believed that their ancestor was much like a wolf. Other animals, such as the fox, came from this ancestor, too. Hundreds of thousands of years ago, man began to tame wild dogs. After the dogs were tamed, they were trained. The strong dogs became working animals. They were trained to pull heavy loads. They learned to keep an eye on the sheep and other animals. Working dogs had other jobs, too. Some dogs were not strong. But they could help man hunt for game. Other dogs were best as pets. Today, there are more than 100 kinds of dogs in the world.
狗
現(xiàn)在許多人都把狗當(dāng)作他們的寵物。狗是人類的朋友，不僅因?yàn)樗鼈兛蓯?，而且因?yàn)樗鼈儗χ魅酥艺\。 狗能為人類做很多工作。它們可以和我們玩，它們可以跟我們一起打獵，它們可以給我們看家。但是以前世界上的狗都是野生的。 狗可以追溯到石器時代。所有的狗都是同一個祖先，人們相信狗的祖先很像狼。其他動物 ，如狐貍，也是來自這個祖先。幾千年前人類就開始馴服野狗，狗被馴服后，人們就訓(xùn)練它們。強(qiáng)壯的狗成為人類工作的幫手，人們訓(xùn)練它們拉重的貨物。它們學(xué)會了幫人們照看綿羊和其它的動物 。 有些狗不夠強(qiáng)壯，但它們能幫人們尋找獵物。還有些狗成了人們的寵物。 目前世界上狗的種類已經(jīng)達(dá)到100多種
