This is the 13898th most frequent German word.
feststellten
"Feststellten" is the past tense of "feststellen," meaning "determined" or "ascertained."
Here, "stellten fest" translates to "determined" or "found out", showing an action of uncovering or confirming information.
Die Wissenschaftler stellten fest, dass das Experiment erfolgreich war.
The scientists determined that the experiment was successful.
In this case, "stellten fest" means "noticed" or "realized", highlighting an awareness or acknowledgment of something.
Während der Arbeit stellten sie fest, dass sie einen Fehler gemacht hatten.
During the work, they noticed that they had made a mistake.
Here, "stellten fest" communicates an act of determining or appreciating based on observation.