I excel at Necessary questions, but fail miserably at Sufficient assumptions. Are there any techniques that'll help me with these? I mostly have a problem on the ones that don't require formal logic.
Are you able to see the gap in the chain for both NA and SA? To see how the premises do or do not link up? In other words, can you prephrase the gap when going into answer choices?
SA and NA have very different approaches, IMO. For SA questions, doing minimal diagramming is helpful, whereas I don't think that's crucial for NA. NA questions require you to really know the argument core really well, and while that's also true for SA, a majority of the questions require concept/term links, which requires us to trace how they're shifting in the stimulus.
Both are about missing links in the chain. Whether you can point out the missing link is ultimately what they share. I can typically pick out the gap in NA (the process seems like intuition at this point), find an AC that addresses it, negate it to confirm. SA is often a matter of diagramming or of grounding term shifts.
Assuming you use POE religiously (highly recommend), are you usually down to 2 answer choices? If you are, I'd insert them back into the stimulus. Re-read the stimulus plus contender #1 then ask yourself, "Am I compelled by the logic gods to believe this? Is this argument valid?" Repeat with contender #2. It's got to totally seal things up, account for every options and force you to accept the conclusion as correct. Usually (sometimes?) stronger language is involved. I hope that helps.
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