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A. Coordinating Conjunctions
Location of a coordinating conjunction
1. Don’t use a coordinating conjunction (for, and, nor, but, or, yet, so) at the beginning of a sentence. These conjunctions can be used to join two independent clauses, so they come in the middle of a sentence rather than the beginning.
Commas with coordinating conjunctions
2. Use a comma before a coordinating conjunction when it is being used to join two independent clauses.
I wrote for ten hours, but I didn’t finish my composition.
I wrote for ten hours, yet I didn’t finish my composition.
I couldn’t decide if I should continue writing, or if I should go to bed.
I was tired, so I went to bed.
I went to bed, for I was tired.
I continued thinking about my composition, and I couldn’t fall asleep.
I didn’t finish my composition, nor did I get any sleep.
3. The coordinating conjunctions and and or can be used to join two nouns, verbs, adjectives, or adverbs. In these cases, don’t use a comma before the conjunction.
I couldn’t decide if I should continue writing or go to bed.
I felt nervous and worried.
I was thinking about my composition and other homework all night.
Check your understanding of coordinating conjunction use
B. Conjunctive Adverbs
Location of a conjunctive adverb in a sentence
1. A conjunctive adverb (e.g., however, nevertheless, therefore, moreover, likewise, furthermore, consequently, etc.) can be used at the beginning, middle, or end of a single independent clause. The beginning or middle is preferred to the end position.
Commas with conjunctive adverbs
2. Use a comma after a conjunctive adverb when it starts a single independent clause.
I wrote for ten hours. However, I didn’t finish my composition.
I wrote for ten hours. Nevertheless, I didn’t finish my composition.
I was tired. Therefore, I went to bed.
I was tired. Consequently, I went to bed.
3a. Use commas around a conjunctive adverb when it comes between a subject and main verb in a single independent clause.
I wrote for ten hours. I didn’t, however, finish my composition.
3b. Use a comma before a conjunctive adverb when it ends a single independent clause.
I wrote for ten hours. I didn’t finish my composition, however.
Semi-colons with conjunctive adverbs
4. A conjunctive adverb can be used to join two independent clauses. In this case, a semi-colon is used instead of a period after the first independent clause.
I wrote for ten hours; however, I didn’t finish my composition.
I was tired; consequently, I went to bed.
C. Subordinating Conjunctions
The location of a subordinating conjunction in a sentence
1. A subordinating conjunction (because, although. until, if, when, while, before, after) is used to join an independent clause and a dependent clause. They can come at the beginning of a sentence or in the middle when they begin another clause.
Commas with subordinating conjunctions
2. When you begin the sentence with the subordinating conjunction and the dependent clause, use a comma after the dependent clause (before the second/independent clause).
Although I wrote for ten hours, I didn’t finish my composition.
Because I was tired, I went to bed.
3. When you use the subordinating conjunction in the middle of the sentence and the dependent clause at the end, don’t use a comma after the first (independent) clause.
I didn’t finish my composition although I wrote for ten hours.
I went to bed because I was tired.