Semicolon and Colons

The Semicolon The semicolon (;) is a punctuation mark that serves as the happy medium between the comma and the period. It signals to the reader to pause longer than for a comma but to pause without the finality of a period. The semicolon is used to separate independent clauses that have a close relationship to each other. It is also used to separate clauses or items in a series that already contain a number of commas.

Use the Semicolon With Independent Clauses Use a semicolon to join independent clauses that are not already joined by the conjunction and, but, for, nor, or, so or yet. Example: The astronaut trainee sat in the spinning, swinging chair; she soon grew dizzy going in circles. Do not use a semicolon to join unrelated independent clauses. Examples: Incorrect- Astronauts train for their missions; tomorrow, rain is expected. Correct- The word astronaut is of Greek origin; it means “sailor among the stars.” Semicolons can be used to join more than two independent clauses. Example: Alexei A. Leonov was the first human being to float freely in space; Edward H. White II was the first American to spacewalk; Valentina Tereshkova was the first woman in space.

Conjunctive Adverbs or Transitional Expression Conjunctive Adverbs: also, besides, consequently, furthermore, however, indeed, instead, moreover, nevertheless, otherwise, therefore, thus. Example: In 1967, the United States Apollo was scheduled to fly as the first manned Apollo spacecraft; however, the command module caught fire during a ground test, and the flight was cancelled. Transitional Expressions: as a result, at this time, first, for instance, in fact, on the other hand, second, that is. Example: We needed to get to the spare tire in the trunk; as a result, we had to unload the trunk.

Conjunctive Adverb and Transitional Expression Because words used as conjunctive adverbs and transitions can also interrupt one continuous sentence, use a semicolon only when there is an independent clause on each side of the conjunctive adverb or transitional expression. Example: Incorrect- The flight was; consequently, cancelled. Correct- The flight was, consequently, cancelled.

Use the Semicolon to Avoid Confusion Consider the use of semicolons to avoid confusion when independent clauses already contain commas. When a sentence consists of two independent clauses joined by a coordinating conjunction, the tendency is to place a comma before the conjunction. However, when one or both of the sentences also contain commas, a semicolon may be used before the conjunction to prevent confusion. Example: The astronauts who were aboard the first manned spaceflight to the moon in 1968 were William Anders, Frank Borman, and James Lovell; but they did not land on the moon.

Semicolon in a Series of Items that Contain Commas Example: Some of the women that the space program has trained include the Russian, Valentina Tereshkova, who orbited Earth in 1963; Sally K. Ride, the first American woman in space; and Christa McAuliffe, who was killed in a tragic accident seconds after liftoff in the shuttle Challenger.

The Colon The colon (:) is used primarily to point ahead to additional information. It directs the reader to look further. It acts mainly as an introductory device. It is also used in several special situations.

Colons as Introductory Devices Use a colon before a list of items following an independent clause. Astronaut trainees go through the following five phases of training: classroom work, flight training, survival training, mission training, and special training. Use a colon to introduce a quotation that is formal or lengthy or a quotation that does not contain a “he said/she said” expression. The more formal the quotation the more likely to need a colon. The speaker began with these words: “I have never been so honored in all my life.” Use a colon to introduce a sentence that summarizes or explains the sentence before it. Capitalize the first word after the colon if the word begins a complete sentence. The technician provided her with one piece of advice: Check the water level often.