What is the most important thing to you in the world why?

hello everyone,I am very pleased to have a speech for you.There is always a most important thing in our mind which possibly make an impacton your life and behavior.so do I.as for me.it's my good hum...额……老师让我们这篇文章里面出现三级词汇，好像、没有吧……还是很谢谢你O(∩_∩)O！！！没事,练练，不过我有个问题你说的三级词汇是专业的吗？