Fifty states make up the U.S.A.
1. The U.S.A is made up by fifty states.
2. The U.S.A. is make up of fifty states.
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Q1: Which one is the passive sentence of the first sentence?
Q2: Are both grammatical? What is the difference between them in meaning?
Neither 1 nor 2 is correct. Here's the correct version:
The USA is made up of fifty states.