fǎn / huí / dì / qiú / qián / yǔ / háng / yuán / zài / tài / kōng / cāng / lǐ / wán / chéng / le / zuì / hòu / de / shí / yàn

返回地球前，宇航员在太空舱里完成了最后的实验。

Before returning to Earth, the astronaut completed the final experiment inside the space capsule.