同学你好，该知识点来自沪江网校《沪江德语【三年全能尊享班 】 》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好~
是的。

when：
句首：When I arrived, the meeting had already started.
句中：I was watching TV when the phone rang.

while：
句首：While I was walking, I saw an old friend.
句中：I saw an old friend while I was walking.

as：
句首：As the sun sets, the sky turns orange.
句中：The sky turns orange as the sun sets.

祝同学学习进步~