Many people see GMAT sentence correction as sort of a grammar test, and so they prepare by learning as many rules as possible and by studying many explanations to sentence correction questions.
The truth is that GMAT sentence correction, while it does involve the use of some language rules, is primarily a test of skill in seeing what is going on in situations and in using logic to make decisions. So to prepare effectively you have to train yourself notice key details and to use effective processes for differentiating between choices and choosing the best one.
Also, while reading explanations can be useful, especially in the beginning of your preparation, you will not learn to rock GMAT sentence correction by simply reading explanation after explanation, because the explanations are not giving you what you really need in order to score high in SC. What you really need is to become good at finding ways to choose the right answers on your own.
I wrote more about how to master GMAT SC in this post.
https://www.beatthegmat.com/how-do-i-mas ... tml#762120