Assuming Every Underlined Portion Includes an Error - If you can't find an error and think NO CHANGE might be the best choice, look at the differences between the answers and try to determine what type of question it is.
Leaving in Extra Words - Questions that test these topics require you to eliminate totally grammatically acceptable phrases that often seem to add information.
Adding Unnecessary Commas - Many students believe that you should put a comma in any place in a sentence where there's a pause, but this approach will result in your missing a lot of questions.
Connecting Independent Clauses Incorrectly - One of the most common ACT English comma issues is called a comma splice, which occurs when a comma is used to connect two independent clauses.
Confusing It's, Its, and Its' - The differences between them can seem complicated, especially if you haven't studied them in a while, but they're actually quite straightforward. Its, with no apostrophe, is a possessive pronoun.
Using They or Their as a Singular Pronoun - In written English, however, this usage is considered a pronoun agreement error: the noun is singular, but the pronoun replacing it is plural.
Not Reading the Question - As with the other sections of the ACT, it's extremely important to carefully read the questions and think about what they're asking. Usually, the best indication of the answer is right there in the question.
Misplaced Modifiers - Misplaced and dangling modifiers—descriptive words or phrases that are incorrectly placed in a sentence—are another type of weird error that often doesn't seem wrong.