Question: Sentence 1: A congregation is a vehicle of group identity.
Sentence 2: The play was just a vehicle to display her talents.
Does vehicle mean the same thing in these two sentences?
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Answer: the same meaning

Question: Sentence 1: The separation of wheat from chaff.
Sentence 2: He hid in the separation between walls.
Does separation mean the same thing in these two sentences?
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Answer: different meanings

Question: Sentence 1: The flock of birds took to the air.
Sentence 2: There was a tension in the air which made me suspect an approaching storm.
Does air mean the same thing in these two sentences?
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Answer:
the same meaning