假如你是李华，你的美国朋友John对我国明代 （Ming Dynasty） 著名医学家 （medical scientist） 李时珍很感兴趣，写信向你咨询。请你根据以下提示，用英语给他写封回信，向他介绍李时珍。
    写作内容提示：
    （1）李时珍生于1518年。
    （2）著作中草药 （Chinese herbs） 总集《本草纲目》，内含近2000种中草药。
    （3）写作历时37年，期间他访民间，走群山，尝百草，亲身作试验。
    （4）你对他的评价。
                             

【考点】人物介绍．

【答案】As we all know，Li Shizhen was a famous medical scientist in the Ming Dynasty.He was born in 1518.In his life，not only did he call on ordinary people and visit mountains but he also tasted different kinds of herbs and even carried out experiments himself.
By working hard，he wrote a famous book called Bencao Gangmu，which is a collection of Chinese herbs.It includes nearly 2，000 Chinese herbs with millions of Chinese characters.
Li Shizhen  is considered to have  made great contributions to the development of Chinese medicine.