premise: How to refill brake fluid<br>Park the vehicle on a level surface and turn off the engine. [substeps] Before proceeding, make sure that the vehicle is in park with the parking brake activated. Though the risk of a free-rolling vehicle is almost insignificant for this procedure, it's better to be safe than sorry.
hypothesis: the risk of rolling is non-existent but better safe than sorry.
reason: the risk of rolling is insignificant, but that means its still possible. i think the system found these two synonymous but they aren't.