十万个为什么·科学阅读30篇（7）

1 Why Do Leaves Change Color in Fall? 为什么秋天树叶会变色？ 2 How Do Rainbows Form? 彩虹是怎么形成的？ 3 Why Is the Sky Blue? 为什么天空是蓝色的？ 4 How Do Magnets Stick to Some Metals? 磁铁为什么能吸住某些金属？ 5 Why Do We Yawn? 我们为什么会打哈欠？ 6 How Do Bats Find Their Way in the Dark? 蝙蝠怎么在黑暗中找到路？ 7 Why Do Stars Twinkle? 星星为什么会闪烁？ 8 How Do Seeds Travel? 种子是怎么传播的？ 9 Why Does Ice Float on Water? 为什么冰能浮在水面上？ 10 How Do Fireflies Make Light? 萤火虫是怎么发光的？ 11 Why Do We Get Hiccups? 我们为什么会打嗝？ 12 How Do Snails Move Without Legs? 蜗牛没有腿是怎么移动的？ 13 Why Do Some Clouds Produce Rain While Others Do Not? 为什么有些云会下雨，有些却不会？ 14 How Do Bees Know Which Flowers Have Nectar? 蜜蜂怎样知道哪些花有花蜜？ 15 Why Does Salt Melt Ice on Roads? 为什么盐能融化道路上的冰？ 16 How Do Tides Change Every Day? 潮汐为什么会每天变化？ 17 Why Do Some Animals Hibernate in Winter? 为什么有些动物冬天要冬眠？ 18 How Do Plants 'Drink' Water from the Ground? 植物怎样从地下‘喝’水？ 19 Why Do Some Rocks Glow in the Dark? 为什么有些岩石会在黑暗中发光？ 20 How Do Ants Build Bridges with Their Bodies? 蚂蚁如何用身体搭建桥梁？ 21 Why Do Volcanoes Erupt at Certain Times? 火山为什么在特定时间喷发？ 22 How Do Butterflies Taste with Their Feet? 蝴蝶如何用脚品尝味道？ 23 Why Do Deserts Have So Many Sand Dunes? 为什么沙漠里有这么多沙丘？ 24 How Do Cacti Store Water for Long Dry Periods? 仙人掌如何长期储存水分？ 25 Why Do Some Insects Walk on Water? 为什么有些昆虫能在水面上行走？ 26 How Do Frogs Change Color to Match Their Surroundings? 青蛙如何改变体色来匹配周围环境？ 27 Why Do Mountains Have Snow on Top All Year? 为什么高山顶部常年积雪？ 28 How Do Coral Reefs Grow So Slowly but Become So Big? 珊瑚礁生长如此缓慢，为何却能变得如此巨大？ 29 Why Do Some Trees Lose Leaves in Autumn While Others Stay Green? 为什么有些树秋天落叶，而另一些树却四季常青？ 30 How Do Geysers Shoot Hot Water and Steam High Into the Air? 间歇泉为何能将热水和蒸汽喷向高空？