Here is the sample of SAT percentile overall and per section. As you carefully notice each sheet, one will show the importance of how English Grammar can make a difference in overall test scores. There are 49 questions on the SAT writing section. Grammar accounts for over two thirds of marks on this section. There are set of rules which students need to know to raise their scores by X%. At Brain Boost,we help all the students individually to understand the rules which can help them to bump the scores.