Given scene/plot descriptions from movies or TV shows, and given a specific question about the scene, summarize the question into a title

[Q]: General spoiler alert so I don't have to hide the whole question...  Towards the end of Avengers: Infinity War, Thanos uses the time stone to rewind time and reassemble the shattered mind stone.  We know that Thanos only retrieved the time stone moments ago on Titan.  We also know that using the time stone is not easy, and requires significant training and ancient knowledge, as noted in this Doctor Strange scene:    Mordo (referring to the time stone):      How did you learn to do that? Where did you learn the litany of spells required to even understand it?      Dr. Strange:      I've got a photographic memory. It's how I got my M.D. and Ph.D. at the same time.      Mordo:      What you just did takes more than a good memory.  You were born for the mystic arts.     Given the above, how does Thanos know how to use the time stone?
[A]: How did Thanos know how to use this item?


[Q]: In The Revenant (2015), there's a scene where Leo finds fish in the river and the fish is trapped in rocks which are arranged in a U shape on the side of the river. So did someone arrange the rocks in a U shape or were they natural arranged?
[A]: Did someone arrange rocks in a U shape?


[Q]: The CIA Director enters an elevator with someone and asks about Jessica Chastain's character.   The assistant claims she is really smart, to which the Director responds with, "We're all smart".   What is the significance of this sequence?
[A]:
What is the meaning of the elevator scene in Zero Dark Thirty?