Nowadays, more and more people enjoy having pets as companion. It‟s often said that dogs are man‟s best friend. But since they‟re our friend, we have the responsibility to take care and concern about them. So what are the disadvantages and advantages brought by keeping a pet?
First of all, the fees for healing a sick pet are surprisingly high. Pets are just like human, they have the possibility to become ill when something goes wrong. Medical treatment is always expensive no matter it‟s for human or for animals. However, if you don‟t want to experience the grief of losing your friend, you need to pay for sustaining its physical condition. Secondly, pets are trouble makers. Despite the fact that some dogs are truly smart and friendly, most of the time pets don‟t understand what our words mean. If we cannot stop them in time, they might turn the whole room upside down. We are the one who end up clearing all the mess.
However, even though they might bring some troubles to our life, they do make our life much funnier. We can train they to get slippers for us when we get home, or guiding our house when no one at home. Some loyal and fierce dogs are even trained to be police dog, helping to catch dangerous criminals.
In my opinion, it‟s all right to keep a pet at home, and we can‟t neglect the responsibility of maintaining the well-being of our good friend.

本作文主要要求陈述养宠物的优缺点， 以及自己的观点。 首先在段首可以点出养宠物的人越来越多这一现象， 再引出中心， 即要对宠物负责。 第二段介绍养宠物的缺点， 例如高昂的医疗费用， 和宠物给家里带来的麻烦。 第三段介绍宠物的优点， 可以训练它们为人类服务， 比如警犬。 最后一段陈述自己的意见， 即再次重复本文中心， 养宠物的同时， 要对它们负起责任