hanuman_2000“
1. This building turned out to be as a school.
What is the meaning of the "turned out to be" here?
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Unless you took this from some really odd context "turned out to be as a school" isn't correct. You must have misquoted it, it should be "turned out to be a school."
It means that, when the building was first noticed, there was some question as to what its purpose was, but on further investigation it was discovered to be a school.