题目

 短文填空。 根据下面短文内容，在短文的空格处填上一个恰当的词，使短文完整、通顺。 A young man once asked his grandpa, “Grandpa, you have made so many achievements in your life, and I really 1 why you are still full of energy.” The following was the grandpa’s answer. I think it has a lot to do with how a person looks at things. I call it “keeping your  2 open”. First, realize that life is filled  3  surprises, and many of them are good ones. If you don't keep watching for them, you'll miss half of the excitement. When you meet with cha若关于x的不等式组的解集为x<4，则m的取值范围是_______.