shuttle pulse

例句：

1. 1. The space shuttle is the first manned spacecraft to travel between Earth and the Moon.
   太空梭是第一艘往返于地球和月球之间的载人航天飞船。
2. 2. The shuttle was designed to transport astronauts back to Earth safely.
   这个飞船的设计是为了安全地将宇航员送回地球。
3. 3. The shuttle's engines were modified to increase its speed for the launch.
   这个飞船的发动机被修改过，以增加其发射时的速度。