Translation:The operation used to take eight hours.
Why is it 'took', not 'takes'? In English you would only really use 'took' if you were talking about an operation that no longer happens anymore, you would use 'takes' if the operation was something that still occurs. Instinctively, the sentence sounds a bit odd to my native English ears :)
Try listening to the words on Forvo.com. I have a hard time with the robot, but I can hear two syllables for plejer and three for plejede when a human pronounces them.
I also notice that the three syllables in plejede are more prominent in the normal speed version of the Duo sentence than they are at skildpadde speed.