讨论——天空离我们不远走在路上,常常仰头看天,因为天空中有云彩。云彩是天空这块油画布上的画儿。在天空中,我们有时会看到烟。现在的大城市里,高大的烟囱渐渐少了,但还是能看到飘动的渐渐消散的烟。看到烟,会让我们产生联想:烟是什么?它很轻很轻,比空气还轻,所以会往上飘,然 Discussion - The sky is not far away from us walking on the road, often looking up at the sky because there are clouds in the sky. Clouds are paintings on the canvas of the sky. In the sky, we sometimes see smoke. In today’s big cities, the tall chimneys are getting less and less, but you can still see the fluttering smoke gradually disappearing. Seeing the smoke will make us think about it: What is smoke? It’s light and light, lighter than air, so it floats upwards.