12 Common Writing Mistakes Bloggers Make Source: Grammar Check If you enjoyed this post, read: 7 Simple Ways To Generate New Ideas 30 Idioms You Need to Know & Their Meaning 33 Commonly Misunderstood Words & Phrases TOP TIP: If you want to learn how to blog, join us for The Complete Blogging Course in Johannesburg or sign up for the online version. Posted on 21st November 2016 (6,308 views) Explore: Blogging, Grammar, Infographic This article has 2 comments Denise van Hulst 21st November 2016 I was taught in English class that there is no comma before and and but in a sentence. AggieCowboy 21st November 2016 #10 is wrong. Or, rather, outdated. The singular “they/their” is acceptable and understood to be singular by the context of the sentence. @Denise: No comma if the clause following the conjunction is incomplete, but a comma is required if it is a complete clause that can stand as it’s own sentence. Then there’s the Oxford comma when writing lists. It’s not always needed; however, not using a comma before the conjunction may completely change the sentence. Comments are now closed.