舱外航天服实际上是最小的载人航天器，是航天员走出航天器到舱外作业时必须穿戴的防护装备如图27所示．舱外航天服质量仅约110kg，除了具有舱内航天服所有的功能外，还增加了防辐射、隔热、防微陨石、防紫外线等功能．舱外航天服主要由外套、气密限制层、液冷通风服、头盔、手套、靴子和背包装置等组成，是一种多层次、多功能的个人防护装备．气密限制层是舱外航天服最重要的部分，它的作用是保持服装气密，限制服装膨胀，使各大关节具有一定的活动度．液冷通风服穿在气密限制层内，在服装的躯干和四肢部位有网状分布的塑料细管，液体流过时可将热量带走．

2014年5月，***在非盟会议中心发表演讲时，引用了埃塞俄比亚的一句谚语：“蜘蛛合力，足以网住狮子”。该谚语揭示的道理是（     ）

任务型阅读

    Last Wednesday, when school children were travelling home by bus from Yucai Middle School,a car hit their bus.Luckily,no one was hurt.

    The accident happened because the driver of a red car,Mr.Zhang,68,became ill and fell down on the steering(方向盘)while driving.His car then hit a white car.And the white car hit the school bus. Luckily, nobody was driving fast. ____

    The driver of the bus, Mr. Li, stopped the bus at once. ____ And then he got out to see if he could help anyone.

    Mr. Wang, the driver of the white car, was not hurt and was trying to push his car to the side of the road.No cars could pass because of the accident. ____

    Mr. Li tried to help Mr.Zhang. ____ So Mr. Li called an ambulance(救护车). ____ It was difficult for the ambulance to reach there. With the help of the police, the traffic could move again. Soon the ambulance(救护车) took Mr. Zhang to the hospital .