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ACT & SAT Grammar Rules


Hands up if you like grammar? Ok … really nobody. Except nobody likes being corrected about their grammar either. The ACT and SAT grammar rules are mostly quite basic – you probably find you can already answer quite a lot of the questions correctly. On this page, I outline a few of the more complicated ACT and SAT grammar rules so that you can understand the reasons behind some of the trickier answers.

Grammar’s a funny thing. You learned grammar intuitively when you learned to speak. You didn’t learn your first language because someone read you a list of verbs! The first time most people encounter grammar is when they learn a foreign language, which can mean that you don’t end up learning English grammar that well. The truth is, you don’t really need to learn it – you already know it. But like most people, you probably need to tidy up your knowledge a little bit. That’s what this series of infographics is designed to do. Comment below if there’s a rule you’re confused about, and I’ll cover it!


This can be a really confusing one: “which” vs. “that”. Want to know when to use which or that? Sometimes it doesn’t matter (unless you’re a purist), other times it does!

grammar which vs that when to use ACT SAT grammar rules


Here’s a thorny issue – correct usage of the word ‘being’. Because it’s such a common word, it has a lot of different uses, and is commonly misused too!

uses usage of being correct ACT and SAT grammar rules


Modifiers are very hard to spot on the ACT or SAT, but once you know that’s what the question’s asking, it’s quite easy to answer. I often find that my students think all of the answer options are correct when they see these kinds of questions, so that might be your tip-off that it’s a modifier question.

ACT and SAT grammar rules modifiers subject object english


Parallel phrasing is a common question on the ACT and SAT grammar sections. The key is to match the tense of the verbs.

Parallel Phrasing


This is probably the most common ACT and SAT grammar rule that I get asked about! Here’s the answer:

Who and Whom ACT and SAT grammar rules


This is an absolute must to master for the ACT and SAT grammar sections; it’s almost guaranteed to come up multiple times on the test, so make sure you can get it right every time!

ACT and SAT grammar rules Semicolons, colons, commas and periods