15m－7m=____m

      阅读下面的文字，完成下列题目。
      ①很多人可能没有意识到，微妙的气味会影响情绪，甚至能在毫无觉察的情况下改变人们的行为。
      ②早在四千年前，人们就已经懂得利用植物精油的气味来帮助恢复精神，愉悦身心。茉莉的香气清新淡雅，能够使人心情放松；檀木的香气持久醇厚，能缓解紧张焦虑的情绪……后来人们又发现，臭气会抑制记忆，让人产生忧虑和压抑的情绪。
      ③气味还会悄悄地影响人们对他人的好恶。美国西北大学曾做过这样一个试验：受试者被要求各自嗅闻某一个装有不同味道气体的瓶子——清爽的柠檬味、不那么好闻的汗味或中性的味道。之后，研究人员向受试者出示了一位长相普通的陌生人的照片。随后，受试者被问及对此人的印象。闻过柠檬味的人都对这位陌生人产生了好感，但闻过汗味的人普遍对其产生厌恶情绪。
      ④另有研究认为，气味甚至能帮助人们感知他人的情绪。科学家提取了第一次跳伞的人在跳伞时的汗液样本，然后出示在受试者的面前。结果，核磁共振大脑成像扫描显示，受试者大脑里通常与情绪有关的杏仁体部位活跃起来。作为对比，来自跳伞者在跑步机上活动时的汗液样本，却不会激活受试者大脑的杏仁体。这说明跳伞人在受到惊吓时散发出了包含着恐惧信息的气味，它在不知不觉中诱发受试者脑部相应区域产生连锁反应。
     ⑤气味甚至会在不知不觉中对人们的行为产生影响。试验结果显示，当受试者闻到异常气味时，无论是好闻的还是难闻的，他们的行为明显会异于平常。荷兰代夫特理工大学的研究发现：在聚会场所中释放橙汁、海水的气味，人们通常会联想到惬意的海滩度假情境，就玩得更尽兴，甚至觉得场地的音乐都更劲了。原来，气味会刺激大脑与情绪有关的领域，人们在受到气味刺激时，常常做出情绪化而非理性的判断，进而影响了后续行为。

    It was a late Wednesday night when the dreading phone call reached our home. I sat up, somehow terrified, so I could hear the phone call better. To my surprise, I heard my mom burst into tears. “Get the car, Dean! Andrea has been in a car accident.”

    We ran every stop sign on the way to the hospital and our tires screeched around every corner. We got to the hospital, but were not allowed to see Andrea. The next morning, after wearing masks, we were allowed to go to the ICU to see Andrea. Well, the least I could say was that everything was injured in her body and she lost all of her memories. It was a fatal accident.

    Over the next two months, I lived more at the hospital than I did at my house. I watched as Andrea worked so hard to gain back everyday motor skills. She never once complained or pitied herself; her determined spirit was shining through. After two weeks in the ICU and two months of the regular hospital treatment, Andrea was able to come home. She missed several months of school, so it was hard for her to catch up. Andrea had tasks to accomplish, and no matter how hard it was, she stuck with them until the job was done. Though busy with dealing with pain and therapy, she always found time to love and play with me.

    I'll never forget the impact that this incident made on my life. I admire her strong-willed personality and her determined spirit. Today she is perfectly normal, despite the scars and the pins holding her leg in place. I couldn't ask for a better sister, hero, or best friend.

选词填空。

珍贵    珍稀

①银杏树，又叫白果树，它是几亿年前的树种，十分____。

②熊猫是____动物。