Colons and Semicolons
The semi-colon (;) is a punctuation mark used to connect two independent clauses, indicating a relationship between the two clauses. The semi-colon indicates a pause that is longer than that suggested by a comma, but shorter than the full stop of a period.
What is an independent clause?
An independent clause is a string of words that could stand alone as a sentence.
- Dave loves to swim.
- Grapes taste great.
- He jumps in the lake daily.
- Cherries do, too.
Using semi-colons to separate independent clauses
In the above examples, a semi-colon may be placed between the two related independent clauses.
- Dave loves to swim; he jumps in the lake daily.
- Grapes taste great; cherries do, too!
When a conjunction is present — such as and, or, because, while or but — is introduced at the beginning of an independent clause, it becomes what is known as a dependent — or subordinate — clause. Commas are used to connect independent clauses to dependent clauses:
- Dave loves to swim, and he jumps in the lake daily.
- Because Dave loves to swim, he jumps in the lake daily.
WARNING: When you try to connect two independent clauses using just a comma, you create an error known as a comma splice:
- WRONG: Dave loves to swim, he jumps in the lake daily.
- WRONG: Grapes taste great, cherries do, too.
- WRONG: Return of the Jedi features Ewoks, Lord of the Rings features hobbits.
- RIGHT: Return of the Jedi features Ewoks; Lord of the Rings features hobbits.
- RIGHT: While Return of the Jedi features Ewoks, Lord of the Rings features hobbits.
You can use semi-colons to connect two independent clauses using transitional words, such as however, therefore, still, unfortunately, because of this and as a result.
- Chainsaws are by far the most effective tool to clear-cut woodland for farm use; unfortunately, chainsaw use carries great risk.
- The elkhound is one of the most loyal, brave and dependable breeds of dog; because of this, the Norwegian Defense Minister has the power to mobilize all privately owned elkhounds in time of war.
Using semi-colons in a series or list
You can use semi-colons to separate elements in a series or a list, especially when each of the elements contains commas.
- The campers came from all over the country: Milwaukee, WI; Raleigh, NC; Boston, MA; Seattle, WA; Tucson, AZ.
- She was given a handful of jobs on the farm: watering the tomatoes, but only when they needed it; weeding the flower border, but no more than twice a month; feeding the chickens, but not too much.
The Colon (:) is a punctuation mark used after a statement that introduces a list, a quotation, an explanation or an example.
- Romeo and Juliet begins as follows: “Two households, both alike in dignity…”
- The gatehouse held unexpected treasures: two musty shotguns, four fishing poles complete with hundreds of hand-tied lures, and a deck of playing cards from the 1930s.
- Names of African instruments are fun to say: adungu, djembe, mbira, amadinda.
TIP: What comes before the colon must be an independent clause — that is, it must be able to read as a complete sentence on its own.
- WRONG: Frodo brought: sandwiches, tea, and two supplementary cucumbers. (“Frodo brought” is not a sentence — it is a fragment!)
- RIGHT: Frodo brought sandwiches, tea, and two supplementary cucumbers.
- RIGHT: Frodo packed his bag with everything he thought he would need on his picnic: sandwiches, tea, and two supplementary cucumbers.
David Travis is the founder and CEO of Prospect Prep, a New York City-based tutoring agency dedicated to helping students earn better grades, higher scores, and acceptance letters from the colleges of their dreams.