Air is very important to everything that lives. But the air we breathe is g【小题1】 dirty. Pe

Air is very important to everything that lives. But the air we breathe is g【小题1】 dirty. People all over the world are looking for w【小题2】 to make it clean again.
Have you e【小题3】 watched the smoke from chimneys rising high in the air? Have you s【小题4】 the smoke from cars and trucks on roads or the smoke from planes? The smoke is not g【小题5】 to breathe. If we want to keep well and strong, we need to breathe c【小题6】 air.
W【小题7】 more and more factories everywhere and more and more cars, trucks and planes, it is getting harder and harder to do with the air p【小题8】 .
Scientists have a【小题9】 found ways to stop or slow down some of the things that make the air dirty. They will not stop working u【小题10】 we have clean air again..getting

(答案→).getting 解析：【小题1】本句的含义为我们呼吸的空气正在变脏，故本句空格处填变的现在分词形式getting。【小题2】本句的含义为全世界的人都在寻找使空气干净的方法，故本句空格处填方法的单词ways。【小题3】本句的含义为你曾经看过烟囱里的烟冒到空气中，故本句空格处填曾经的单词ever。【小题4】本句的含义为你看见汽车或飞机所排放的烟，故本句空格处填看见的过去分词seen。【小题5】本句的含义为呼吸排放到空气中的烟是不好的，故本句空格处填好的单词good。【小题6】本句的含义为我们需要呼吸清洁的空气，故本句空格处填清洁的单词clean。【小题7】本句的含义为随着越来越多的工厂和汽车，飞机，处理空气污染越来越难，故本句空格处填伴随的单词With。【小题8】本句的含义为处理空气污染越来越难，故本句空格处填污染的单词pollution。【小题9】本句的含义为科学家已经找到阻止或减慢空气污染的方法，故本句空格处填已经的单词already。【小题10】本句的含义为直到我们有清洁空气的时候，他们才停止采取措施，故本句空格处填直到……为止的单词until。

我明天再问问老师，叫他解释下这个问题