A relative pronoun is a word like “that” or “which” or “who”, so a relative clause is a clause that begins with a relative pronoun. In the sentence “The dragon who breathed blue fire has retired,” “who breathed blue fire” is a relative clause. Learn more about these constructions by watching the video!

We use the relative pronouns to connect clauses together, like "the man *who sold the world* is coming over for dinner." David, KA's Grammar Fellow, explains.

A run-on sentence doesn’t separate any of its independent clauses with the punctuation that it needs, and a comma splice incorrectly separates two independent clauses with a comma, instead of a comma-and-coordinating-conjunction.

David and Paige, KA’s resident grammarians, talk about how to address and sign off on letters using commas!

We use semicolons to punctuate a complex list, which is when list items contain commas. For example, “I visited Paris, France; Paris, Texas; and Paris, Illinois.” Paige explains.

Verb aspect allows a speaker to give even more information about when an event took place or is going to take place. The simple aspect of a verb is the same as its past, present, and future tenses, such as "I walked," "I walk," and "I will walk." .

A simple sentence contains one independent clause. A compound sentence contains more than one! Put another way: a simple sentence contains a subject and a predicate, but a compound sentence contains more than one subject and more than one predicate.

This video will teach you all about the different ways you can use the sound of words for effect. Alliteration is when you use a bunch of similar consonants in a row; assonance is when you use a bunch of similar vowel sounds in a row; onomatopoeia is basically sound effects. You'll see.

Before we get any further with pronouns, let's cover what the difference between a subject and an object pronoun is, because the distinction between those two concepts will start coming up a good deal.

A subject is the noun phrase that drives the action of a sentence; in the sentence “Jake ate cereal,” Jake is the subject. The direct object is the thing that the subject acts upon, so in that last sentence, “cereal” is the direct object; it’s the thing Jake ate. An indirect object is an optional part of a sentence; it’s the recipient of an action. In the sentence “Jake gave me some cereal,” the word “me” is the indirect object; I’m the person who got cereal from Jake.

A subject is the noun or pronoun-based part of a sentence, and a predicate is the verb-based part that the subject performs. Let’s explore how that works in context.

Agreement is the art of making sure that sentence parts agree with one another; you want to make sure that your subjects and verbs match up.

Subordinating conjunctions join two parts of complex sentences––independent clauses to dependent clauses. David explains how.

It's totally okay to end sentences with prepositions! David, Khan Academy's grammarian-in-chief, explains the history and the context behind this long-held grammar myth.

Much has been made of the distinction between "that" and "which" in English, but it can mostly be summed up in two points: 1. "That" doesn't work so well with commas. 2. "Which" doesn't work so well with people. David the Grammarian explains.

This is one of the most frequently-confused trios in the English language. Follow along, and learn to suss out the differences between these three words.

Three essential types of sentence are declarative sentences (which are statements), interrogative sentences (which are questions), and imperative sentences (which are orders). Join us as we give examples of each!

David and Paige, KA’s resident grammarians, introduce the three ways to end a sentence: the period, the exclamation point, and the question mark.

Another troublesome triad, "to", "two", and "too". Let's set these` frequently-confused words straight!

This is, bar none, the greatest video Khan Academy has ever made, although I may be slightly overstating that. Learn how to master this style by following along.