1. If I had a lot of money, I could buy a car.

Question

2. If I could buy a house, I would be happy.

3. If I were a rich person, I could buy a smart phone.

3-2. If I " was" a rich person, I could buy a smart phone.
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Are they all grammatical? Can we use 'was' as in #3-2? Is it correct in a test?

Answer 1

No.

http://writingexplained.org/was-vs-were-difference