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A proverb says, "Time is money". But in my opinion, time is even precious than money. Why？ when money is spent, we can earn it back. However, when time is（go） , it will never return. is known to all that the time we can use is limited. Therefore we should make use of our time to study hard so as to serve our country in future. But it is a pity that there are a lot of peopledo not realize the value of time. They waste their precious time smoking, drinking and playing. In word, we should form the good habit of(save) time. Do not put off what can be done today tomorrow.