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Also,please correct my mistakes on grammar. Thanks a lot ! 

Please expand on an aspect(s) of your academic or extracurricular background that you feel is especially important to you and that will help us get to know you.

Instead of telling all the serious situations in China or serious topics about me, I prefer to inform you on a special family member of mine --- a dog called Mantou. I still remember the first day I spent with him. When I rubbed the sleep from my eyes and murmured about the endless noises he had made the whole night, I discovered him peeing on my lovely carpet just beside my lovely bed with an innocent look. I must admit that the beginning of a day with a dog was troublesome. Nevertheless, Mantou has gradually and dramatically influenced our daily life. In order to be a good owner, I have to collect an abundance of strange information on the feeding of dogs. I have never learn before that the period between infection and the first symptom of rabies can last two years, that dogs could develop cancer like human beings, and that dogs need to be vaccinated against some incurable diseases such as Canine distemper and Canine parvovirus enteritis. I started to understand every movement of this little creature. Usually, putting his hands on my thighs and looking into my eyes wishfully are enough for Mantou to express that he wants to play his favorite game---fetching the toy.

One day when I was doing my biology homework, I found that on the bottom of the page I was working on was a piece of short knowledge which discussed the similarities between the genes of dogs and those of human. Attracted by the interesting knowledge about dogs, I forgot to do my task and went though all the notes of every page in that book. I suddenly realized how deeply I am into biology! 

In fact, when I was just a primary school student, I enjoyed watching the science program on CCTV 10, especially the documentary about rare genetic diseases. One episode made a deep impression on me: a hairy boy born in a small Indian village. The furry look made the boy's life rather difficult. Every beginning of the semester was the most terrible time for him because the little boy had to hide behind his parents to avoid being stared by others. I do not know how his life is now, but what I do know is that just sitting in front of the TV is not enough! I cannot wait to go to a university to find out the secret of genes! 

Not until grade 11 did we start to learn genetics. When the teacher announced that we would have an experiment on the extraction and verification of DNA, I was so excited that I dragged my teammate crazily to rush to the lab. After carefully examining the experimental equipment and material, my teammate and I alternately prepared for the next steps. Unluckily, we only drew out one piece of DNA and had no time to start the verification when the bell rang. While most students neglected their work and hurriedly left the lab for their lunch, our group was waiting for the water to boil to see whether the mixture of the DNA and pyruvic acid would turn blue when heated. As time passed by, not a single student was left in the biological laboratory except our group, and I knew I could not make it to lunch by the time we would be done. However, the little Indian child suddenly arose in my mind, reminding me to adhere to my aspiration. Happily all our hard work and persistence had led to a successful ending. We became the only group that completely carried out the whole experiment.

I am sure that all of my relatives and friends will try to persuade me not to study biology because of its toughness and difficulty, but I never fear to study hard no matter how arduous it is and never even to think about how much money I will earn from it in the future. I just want to uncover the mystery of genetics and be able to let the poor live a better life. My wish to save more life is the most essential reason why I want to attend a good Institute with advanced technology and equipment. Some people said that the masters of dogs will be more and more similar to their pets as they spend more time together. Although it sounds ridiculous, I have to admit that I am learning from my dog. He always expresses what he wants simply and chases what he likes. No matter how we hide his favorite toy, he would try his best to find it. What about me? Once I set a specific goal, I try my best to struggle for my dream on the shoulders of precedent giants.