Mary likes to invent things. She creates a new language and teaches it to her friend, Jean. Mary and Jean like to talk to each other in their own language because they think no one understands them and it is funny. When they go shopping, they say things like: "Look! He is fat.” “This CD is awful." "I want to eat free hamburgers.”A clerk comes but he can't understand what they say. He asked them: “May I help you?”Mary and Jean just laugh. What fun it is to create something new.

设定艾滋病日可以更好的宣传预防艾滋病知识，世界卫生组织将“世界艾滋病日”定在每年的（    ）

填空：

（1）施莱登和施旺共同创建的“细胞学说”，阐述了动植物结构和功能的基本单位是____ ．

（2）影响生物生存的因素主要有____因素和____因素．

（3）常用的玻片标本有____ 、____和____三种．

（4）在制作临时装片时，所要观察的材料必须是____ 而____ 的．

（5）生态系统中物质和能量是沿着____ 和____ 流动的．