The reader might as well imagines, under the zero gravity condition, buries the head Harbo inside, then twists more than 100 small hexagonal cap screw nail.

• 读者不妨想象一下，在零重力条件下，将脑袋埋进“哈勃”里面，而后拧掉100多颗小六角帽螺丝钉。