Personally, I believe one should be able to write comprehensible sentences, regardless of vocab.

On a scale of 1/10 (1 being the lowest), a person should be 6-7/10 in order to attempt the paper.

I've seen people making grammatical errors in every other sentence they write - and yet they manage to clear the paper. What matters then is their maturity, argument strength/backing and how wide, open, and all-encompassing view they have of issues.

Again, this is all what I believe personally.

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