THE VOCABULARY DETECTIVE
The robotics report

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malfunction
reversible
preliminary
conclusive
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The delivery robot stopped halfway along the classroom track. “We need a new motor,” Sam said. “This one must be ruined.”
The coach called the stop a malfunction: the robot had failed to do its job. But that word did not explain why it had stopped. She suggested a preliminary check—a first look before taking the robot apart.
Sam noticed several labeled sockets beside the controller. If a plug was in the wrong one, moving it back would be a reversible change. They could undo it without buying a new part. A broken motor would be a different problem.
The team wanted a conclusive test, one that would settle the question they were asking. Could they get the robot around this track again? That was something they could test today. Whether it would work forever was another matter.