I wish to pursue a career in the legal profession because law holds a particular fascination for me and I consider it to have an elite professional standing. My interest in the law has been long-standing. When I was a child, I accompanied my uncle to courts and later on imitate the inquisitive, argumentative, critical as well as negotiating characters of lawyers. Gradually, I became interested in law and decided to be an excellent lawyer in the future.
第一句有点拖泥带水，consider it to have an elite professional standing.不好理解。一般说来，第一段应该总括全文，点名你的优势和竞争力，下文接着具体解释分析。但是这个第一段似乎就是在介绍你是如何对法律感兴趣的。此外，PS最忌讳形容词堆积，inquisitive, argumentative, critical这几个词语不太恰当，而且一段中出现两个interested.
To Whom It May Concern,
I am privileged to write in support of my friend and student, Miss Wang. She studied in my classroom for nearly two years, during which time I witnessed her tremendous growth and development. This development came not only in the field of academic achievement, but in maturity and character as well.
Privilige这个词语太大了，强烈建议不要用。Miss Wang这个词语放在前面，比较好，应为第一句头重脚轻。Classroom这个词语不好，太中国化了，怎能说在他的教师呢。两个development 不好。
Dear Sir or Madam:
Miss QI began her college study in 1999, majoring in International Trade at Lanzhou University. Now, she has graduated from the Economics&Management Department with Bachelor degree in Economics.
I was born in a family in great relation to chemistry. My father is a chemistry professor and my aunt is a druggist. From my young age, my father had a deep influence on me, and I can contact with chemistry in much earlier age than other children around me. He taught me what the composition of salt is, how to put off fire ignited by different causes, which substance we can call organic material and inorganic material .Just like the saying says "Constant efforts bring success", from the beginning of my study of chemistry to high school graduation ,my chemistry score is always the NO.1 of my grade. And in 2000, I won the second prize of National Oylmpic Chemistry Competition.
首先一篇ps的开头一般来说应该总结全文精华，当然有的ps也是一个故事或者精彩试验开头。尽量避免开头就过分细致化。其实第一段你完全可以总结说你出生在有着浓厚化学背景的家庭，从小耳濡目染打下坚实基础。其次，个别语法问题，I can contact with chemistry in much earlier age than other children around me.这里的contact用的不好。此外，你这一段的落脚点是初高中以及奥林匹克竞赛，更不符合ps的写作要求，你总要在开头描述或者总结一下吧，即便是写奖励，你也要写大学的阿，另外这些奖励都在简历中写出来了，绝对不要再放在第一段这么重要的段落重复。
这一段缺乏中心句，开头过于强调××大学化学系了，描述的重点应该是你，体现你多么牛，具备了什么样的能力，这样老板才会要你。 As a freshman后面部分，相信你写的是真情实感，大学时期都这样，包括笔者在内，但这与ps不相关啊，这读起来感觉像是回忆录。如果你申请心理学专业，可以以此为基础进行包装，但你学习的是化学。要的就是你单刀直入，介绍你的成长，主要是专业方面的，而不是个人性格成熟。你要解释你学习成绩不好，最好想其他方法。你可以欲扬先抑，说自己第一个学期不好，然后利用整个暑假努力学习，终于取得成绩，这种经历磨炼了你，增强你克服困难决心。这种思路更好。