阅读理解题第1题 (20) 分 We dont have beds in the space shuttle, but we do have sleeping bags. During the day, when we are working, we leave the bags tied to the wall, out of the way. At bedtime we untie themand take them wherever weve chosen to sleep.On most space shuttle flights everyone sleeps at the same time. No one has to stay awake to watch over the spaceplane; the shuttles computersand the engineers at Mission Control do that. If anything goes wrong, the computers ring an alarmand the
