First, nice job compiling all these links. That's great that you went through that trouble, and it really looks like people appreciate that.
Second, I just want to throw a quick caution your way: When I took the GMAT, I had no idea there was a difference between "instead of" and "rather than." This is one of several hundred idioms tested on the GMAT, so it's worth knowing, but I'd recommend simply noting that the GMAT generally prefers "rather than" and then spending your time on more applicable grammatical concepts. This caution applies across the board: It's generally a better use of time to study the grammatical rules that are most tested than to spend a ton of time with a few select idioms.
Let me know if you have any follow up questions here, and happy studying!
Brett Beach-Kimball | Manhattan GMAT Instructor
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