简述新材料发展的方向。
参考答案：
随着社会的进步，人类总是不断地对材料提出新的要求。当今新材料的发展有以下几点：
（1）结构与功能相结合。即新材料应是结构和功能上较为完美的结合。
（2）智能型材料的开发。所谓智能型是要求材料本身具有一定的模仿生命体系的作用，既具有敏感又有驱动的双重的功能。
（3）少污染或不污染环境。新材料在开发使用过程中，甚至废弃后，应尽可能少地对环境产生污染。
（4）能再生。为了保护和充分利用地球上的自然资源，开发可再生材料是首选。
（5）节约能源。对制作过程能耗较少的，或者新材料本身能帮助节能的，或者有利于能源的开发和利用的新材料优先开发。
（6）长寿命。新材料应有较长的寿命，在使用的过程中少维修或尽可能不维修。
My name is Anna. I am 13 years old. I am a student 1 Grade 7. I like to play tennis and I 2 to school every day. I am strong and have 3 of hobbies. I think I need about 2,100 calories every day. 4 breakfast, I usually eat a piece of bread and some eggs and I drink a cup of milk. This gives me about 00 calories to 5 the day. I often have a big bowl of soup with noodles, 6 and a banana for lunch. I 7 love noodles. This meal 8 me energy for the 9 and for a game of tennis after school. 10 dinner, I always have rice, meat and vegetables. I do not like hamburgers and Coke because they are very 11 in fat and 12 . I never eat chocolate, but sometimes I have cakes. 1 3 dinner, I take in about 70 calories. Later in the evening, I often have a snack. That means I take in 14 2,100 calories every day. I need to eat a lot of healthy food. It is 15 important to exercise every day. Exercise helps you stay fit!
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