Magoosh lists several grammar points (like vs. as progressive tenses etc.) each one containing practice questions. Choose one of the grammar points. Complete 2 questions and study the grammar examples & answers to the questions.

https://magoosh.com/gmat/practice-tests/gmat-sentence-correction-sample-questions/

Magoosh lists several grammar points (like vs. as, progressive tenses, etc.), each one containing practice questions.

Choose one of the grammar points. Complete 2 questions, and study the grammar examples & answers to the questions. (You might need to scroll to the bottom of the page to find the answers.) Then come back to this page and tell me:

1) what grammar point you chose

2) how you eliminated at least two answer choices from each of the questions