人老了，眼睛就会花，如果没有老花镜，想把细线穿进针孔里，不知道要费多大的力气。这里，如图所示是一款缝衣针，其特殊的针孔设计极大的方便了穿线。针孔附近采用了一种特殊的材料，可以拉伸。穿线的时候，只有轻轻往下推一下，针孔就可以变成纽扣一般大，眼睛再花的人，也能轻松的把线穿过去。穿过之后，拉一下，针孔就又恢复原型了，一点也不影响使用，该产品主要体现了设计的（   ）

   

某22肽被水解成1个4肽，2个3肽，2个6肽，则这些短肽的氨基总数的最小值及肽键总数依次是 (     )

生命好像一场旅行。中学，是一段充满挑战的人生旅程，我们要把时间变成更加从容的微笑、更加踏实的脚步，就应（    ）

①笑迎新生活，做更好的自己   ②努力学习，不懈地追梦、圆梦

③早早立志，磨砺意志和品格   ④与友同行，体悟生命的美好

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What is the best way to study? This is a very important question. Some Chinese students often1very hard for long hours. It is a2habit, but it is not a better way to study. An efficient(讲效率的) student must3enough sleep, enough food and enough rest. Every week you 4to go out for a walk or visit some friends or some nice places. It's good5your study. When you return to your studies, you'll find yourself6han before and you'll learn more.

Maybe we can7that learning English is8taking Chinese medicine. We don't mean that it's bitter (苦的). We mean that like Chinese medicine, the efficiency of your study9slowly but surely.10slowly but surely every day and effects will come just like Chinese medicine.

如图是关节模式图，请你分析回答．