试题题干
Translate the following sentence into Chinese.
Later, when they leave the zone of the earth’s gravitation, they are unable to stay in one place.
参考答案
试题解析
考点：the zone of the earth’s gravitation地球引力区；be unable to无法······。
句子结构：when引导时间状语从句，主句为 they are unable to stay in one place.