I' m David, a baby penguin (企鹅). It is snowing outside. I am staying____my nest (~) and waiting for my parents. They went out yesterday to ____food for me. I feel so cold and hungry now because we don't have any food at all. In the last few years,____developed the economy (发展经济), but they forgot the____

    They cut many trees down and ____ lots of factories. The____ from those factories soon changed the climate (改变气候). So it's harder for my parents to find food. What's worse,____ penguins died because of the climate change. But now, people in the world seem to know their mistakes (错误) and begin to do something to save the world. I think we can live a better life in the____

孔子的政治理想是：“远人不服，则修文德以来之。既来之，则安之。”孟子曾批判春秋战国时代连绵的战火为“春秋无义战”。这反映出孔孟：（   ）

看图填空．

一共有____个图形．

三角形占____．

圆占____．

正方形占____．

长方形占____．

随着科学的发展，许多新物质被发现或被合成出来，为新能源开发和新材料研制开拓出更大的空间。
物质的分类标准有多种，自拟两个分类标准，将一氧化碳、氧气、水、二氧化碳四种物质中的三种包括在标准内，而另一种不在标准内。
（1）标准一____，包括的物质（用化学式表示，下同）____；
（2）标准二____，包括的物质____。