Can somebody explain the usage of 'in' and 'at' related to GMAT SC?
We use IN this way.
Sally are you in the bathroom? Remember that in is really from the word inside. So you use the in whenever you would have used the word inside.
We use AT this way.
Charlie calls his son on the cell phone. He would like to know the whereabouts of his son because it is very late at night. His son answers the phone. Charlie says, "David where are you at? You should have been home hours ago." David says, "I am at the hospital because Janeen fell and broke her leg. I don't where she is at inside this hospital. I have been waiting for hours to have her come to the waiting room with a cast on her leg." Charlie asked, "Have you called her parents to tell them where she is at?" "Yes," said David
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