Self-Introduction

This is my first time that i writing a composition here. I hope someone will correct the mistakes that  I will make. Now, let me introduce myself so that you guys will know more about me. I am a clinical research associate, working for at a medicine factory. We are going to start a new clinical trial in July. It’s about a kind of drug that comes from plants and it is for treating male infertility. We have finished investigating its efficacy and safety. It’s a project that is being done in cooperation with my firm and the Shanghai Institute of Andriatry in Renji Hospital. If you know someone who suffers from  male infertility, tell them that maybe I can help them. haha I am a warm-hearted person and that's why I studied at a medical school over the past 4 four years now.
That's all I want to say today. Happy Children's Day, everyone!

{when it comes to numbers, you have to write it in letter form. it is best whenever you write an essay. also, in essays, we cannot write "haha" or "wanna" its grammatically incorrect.}

self-introduction

This is my first time that i writing a composition here. I hope someone will correct the mistakes i make. Now, let me introduce myself so that you guys will know more about me. I am a clinical research associate work for at a medicine factory. We are going to start a new clinical trail in July. It’s about a kind of drug that comes from plants, and is for treating male infertility. We have finished investigating its efficacy and safety. It’s a project that is being done in cooperation with my firm and the Shanghai Institute of Andriatry in Renji Hospital. If you know someone who suffers from  male infertility, tell them that maybe I can help them. haha I am a warm person, and that's why I studied at a medical school over the past 4 years.
That's all I wanna say today. Happy Children's Day, everyone.

Remember to put a period directly after the end of each sentence, and also to capitalize the first letter of every new one.
Otherwise, good job! Keep it up