From what I see, overall, you practice a lot but clearly you do not get the most in terms of benefits from all the process.
1) I am always more convinced that the non-official material must be used only to consolidate concepts and to speed up the process.
For instance, solve questions about exponents to know every single possible rules or trick. The go for the Official questions in that specif area.
2) Slow on quant means only one thing: lack of confidence and not a perfect mastering of the concepts overall.
3) Usually, the students in the mid-low range tend more heavenly to use a strategy such as picking numbers. Sometimes is good but also the flexibility you should have is king. Sometimes picking numbers you waste time and instead of thinking conceptually up-front the question is faster in solving it.
4) The same is for SE and TC: maybe to solve the same question you could use the math strategy: positive versus the negative side of the sentence. Or the time shift. Or the overall meaning. Or the block of four strategy. Or pairing strategy. Or word contrast. Maybe 3 or four strategy at once in the most difficult 3 blanks.
5) as for RC, that is a beast. It requires time and a good master of the English Language, especially in complex and long passages. The tips are water in the desert.
Regards
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