1. (2017八下·泰兴期中) 完形填空。先通读下面的短文，掌握其大意, 然后从下面四个答案中，选出可以填入空白处的最佳选项。

    We are lucky to live in a rich country where we have many things. However, most of us usually1 some things.

    Electricity(电) is one thing that we waste 2. Lights, TVs, 3 and other things are often kept on even when no one is using them. We should turn them off when we do not need them. It 4 less than a second to do it. Anyway, not wasting electricity saves money, because we do not have to 5 the electricity we do not use.

    The second thing that we often waste is water. Fresh water is precious(宝贵的) ， 6it shouldn't be wasted. It is only a simple matter of turning off a tap. I am sure 7 can do this easily if he wants to.

    8 big waste is food. My mother 9cook so much food that much of it was thrown away. I told her we had wasted so 10 food. She thought I was right and now cooks 11 what we can eat.

    It is not 12   to waste anything. I find there is a simple 13of not wasting things. That is to use only what we 14. Do not touch what we do not need. 15 this way we can stop being wasteful.