这种天平使用时必须十分当心。

Great care must be taken in the use of the balance.

youdao

这种仪器使用时必须格外小心。

You must use this instrument with great care.

youdao

该对等恢复类型在使用时必须配置明确。

This style of peer recovery must be explicitly configured.

youdao

This material will be necessary to do the listening exercises for the course, which is sort of the backbone of the course.

做听力练习时我们必须使用这些材料,听力训练是课程的核心内容

耶鲁公开课 - 聆听音乐课程节选

So it`s sort of a key issue for children and for adults actually to make sure that When we use a software that has more than one language it has to be completely in each language.

所以无论对成人还是儿童来说,这都是关键问题,当我们使用一款宣称拥有多语种的软件时,必须确保它的每一种语言都是完整的。

麻省理工公开课 - 媒体、教育、市场课程节选