阅读下面短文，掌握其大意，然后从各题所给的四个选项中选出可以填入空白处的最佳选项。

Time is the most precious thing that we ___(1) own. Once it is lost, it can never be ___ by anyone. Yet many young people waste hours every day on things of little value. They do not realize that time, ___ money, can neither be saved nor borrowed. Successful people are exactly those who know how to make full use of every single minute. If we form the habit of planning our time carefully, we will find there is always enough time for what really ___ to us. In a word, to value time is to ___ our own life.

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