科学家们一定在继续载人航行的研究。的翻译：Scientists must continue to study manned navigation. 什么意思？中文翻译英文，英文翻译中文，怎么说？

青云英语翻译

Scientists must continue to study manned voyage.

Scientists must continue to study manned navigation.

The scientists are certainly continuing the research which carries the human to navigate.

Scientists continue to be manned by the research.

Scientists must continue to study manned navigation.