1. It is clear that imperatives other than profits or nationalism will have to compel human beings to leave their tracks on the planet's reddish surface. 很明显，除了利益和民族主义，其他紧急的事物将迫使人类在地球表面留下他们的足迹。
2. Although their missions blended commercial and political-military imperatives, the explorers involved all accomplished some significant science simply by going where no scientists had gone before. 虽然他们的任务混合了商业和政治军事的需要，但相关的探险者都完成了一些重要的科学任务，因为他们去了以前没有科学家去过的地方。
3. There are several imperatives underlying this principle. 这一原则下有若干隐含规则。
4. Yet strategic imperatives may prompt some countries to overlook such concerns. 但要必须解决的战略储备问题可能促使一些国家忽略掉这些担忧。
5. The model structures described in this articles are guidelines, not imperatives. 这些文章中介绍的模型结构是指南，不是强制的。
