Sie schliefen. Learn Unstarted Literal Breakdown Recording English German Learn they sie Learn Summary The German translation for “They were sleeping.” is Sie schliefen.. The German, Sie schliefen., can be broken down into 1 parts:"they" (sie). Practice Lesson "They were sleeping." Practice (1) Lesson Learn Lesson words This lesson has no individual words. Lesson phrases They were sleeping. etc. View all lesson phrases Acknowledgements English source https://lingopolo.org/dutch/word/they-were-sleeping Audio Google text-to-speech