Problems with Grammar
Sometimes when people think of “good writing” they think only about grammar.
But grammar is really a very minor aspect of “good writing”—and it’s something you don’t really need to worry about until the editing stage of your writing process.
Correcting your grammar and punctuation helps you to meet your reader’s expectations for academic writing, and it often can clarify the meaning of your sentences.
Anyone can learn grammar rules and apply them, but the truth is, grammar comes easiest to people who do a lot of reading.
The Writer's Handbook website
presents common grammar errors that you might be asked to fix.