题目内容：

短文改错。

请修改以下短文：文中共有10处语言错误，错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏词符号（∧），并在该词下面写出修改的词。删除：把多余的词用斜线（\）划掉。修改：在错的词下面划一条横线（_），并在该词下面写出修改的词。注意：1.每处错误及修改均仅限一词；2.只允许修改10处，多者（从第11处起）不计分

The time we have is usual limited. However, even an hour is of much valuable. We should make full use of your time to do useful things. As students, we mustn’t study hard so as to serve for our society and our nation in the future. But it is pity that there are a lot of people who didn’t know the importance of time. They spend their valuable time smoke and drinking. They don’t realize that wasting time is the same as wasting a part of their life. Remember, don’t put off which you can do today until tomorrow.