反射的结构基础是____．它通常是由____、传入神经、神经中枢、传出神经、____五个部分组成．

    为什么我总是受苦，总是遭人白眼，总是让人告状，永远受到责备呢？为什么我永远不能讨人喜欢？为什么我尽力博取欢心，却依然无济于事呢？伊丽莎自私任性，却受到尊敬；乔治亚娜好使性子，心肠又毒，而且强词夺理目空一切，偏偏得到所有人的纵容。她的美貌，她红润的面颊，金色的卷发，使得她人见人爱，一俊便可遮百丑。至于约翰，没有人同他顶撞，更不用说教训他了，虽然他什么坏事都干：捻断鸽子的头颈，弄死小孔雀，放狗去咬羊，采摘温室中的葡萄，掐断暖房上等花木的嫩芽。有时还叫他母亲“老姑娘”，又因为她皮肤黝黑像他自己而破口大骂。他蛮横地与母亲作对，经常撕毁她的丝绸服装，而他却依然是“她的宝贝蛋”。而我不敢有丝毫闪失，干什么都全力以赴，人家还是骂我淘气鬼，讨厌坯，骂我阴丝丝，贼溜溜，从早上骂到下午，从下午骂到晚上。

根据短文理解, 从A、B、C、D四个选项中选择最佳答案填空。

    Mr. Brown lived in a small town. One day he  1 a long journey. It was very late when he was going home.  2 he found that a man 3behind him. Mr. Brown went faster, and the man walked faster too.  4Mr. Brown walked slowly and the man walked slowly 5  .

    Now they were coming near a garden. Quickly, Mr. Brown ran6  it. He tried to get away from the man in this way, but he failed. He was very afraid. He rushed and the man rushed after him. Then Mr. Brown stopped. "Excuse me, "he said, "what do you want 7?"

    " 8 , sir, "answered the man, "You see, I have to  9 Mrs. King a bag and I asked the man at the station. He told me, "go right after that man. He lives in the house just next to  10 . "

贮藏蔬菜或水果时，将空气抽掉一部分并增加二氧化碳的量，会延长贮存时间是由于（　　）