The professor explains thaw lake formation as a cycle of events that occur repeatedly. Summarize this cycle, starting with the event filled in below. Click on a sentence. Then drag it to the space where it belongs. The first one is done for you. One sentence will not be used. Permafrost shrinks and cracks as temperatures drop.
Permafrost shrinks and cracks as temperatures drop
Ice in the active layer melts as temperatures rise
Meltwater flows into cracks in permafrost
Freezing water expands cracks in permafrost
Ice wedges inside permafrost completely melt