这些替代品已经在6号线上投入使用了。
In early space programs, such as the Apollo missions of the 1960s and 1970s, and in the Space Shuttle missions today, scientists developed objects for the astronauts to use on the moon and in space.从20世纪60年代和70年代的阿波罗计划等早期太空计划,航天员研发了在月球上和太空中使用的物品。
Take it with you to use on the door handle as well.拿着这片纸巾,握门把手的时候还要用到。