脊椎动物运动系统的组成有（  ）

 ①皮肤   ②骨骼肌   ③骨   ④骨连接．

“飞蛾捕火”是种什么行为？蛾蝶类昆虫之间信息交流是靠什么？（）

阅读理解

    Many people like going shopping at weekends after five days'hard work．Supermarkets are good places for shopping．

    Before you go into the supermarket，get a trolley．Trolleys are usually outside the entrance(入口)．It's good to push your trolley around and take what you want．If you only plan to buy a few things，get a basket．Baskets are usually in the supermarket．You can buy different kinds of things in the supermarket．You can buy fruit and vegetables，meat and fish，bread and cakes，ice cream and magazines．

    There is a big supermarket near my home．My parents like shopping there but my sister Liz and I don't．There'll  be a sale in it on Saturday．My parents are going to buy some carrots and tomatoes．

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如图为心脏结构示意图，医生给某人右手臂静脉注射一种药物治疗头痛。药物通过心脏的途径是（  ）