One of the problems is that the very concept “choosing between wa and ga” is in itself something of a misunderstanding.
Wa and ga are not two similar particles.
They are two different species of particle.
If we understand this we can get a lot closer to knowing how they really work and why one rather than the other is used in any given case.
This is a fairly complex question so we are dealing with it over two lessons. This first lesson gives the foundation of how ga and wa really work.
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