Punctuation marks: When and how to use the semicolon and colon in sentences

Punctuation marks are symbols that are used in a sentence to make it comprehensible. In other words, the comprehensibility of a sentence is wholly dependent on the correct use of punctuation marks. They are also signals which help to show how written words are intended to be spoken.

Punctuation marks are very powerful in all languages, especially the English language. If wrongly used, they are capable of altering the spoken pattern of a written discourse and the intended meaning of a speaker. Unfortunately, most language users seem not to be concerned about this sheer fact as they mostly present their writings without punctuation marks or with the wrong punctuation marks. In case you don't know, the absence of or wrong use of a punctuation mark in a sentence has some hilariously grave consequences:

1. It can cost a speaker his mom's life. For example, if a speaker fails to add a comma after "eat" in the sentence, "Let's eat mom", it simply means that he has killed his mom and prepared her for breakfast, lunch or dinner. This is what the absence of a punctuation mark in a sentence can cause. To avoid such interpretation, the sentence should be written as "Let's eat, mom." This sentence, unlike the former which is devoid of the comma, requests the speaker's mom to join him in the meal.

2. It can make you love a woman's monthly flow (menses). If you write or say "I love her period." instead of "I love her. Period!", you have only succeeded in telling your audience or listener that you love her menses. This may not be the actual meaning of your statement, but your inability to use the full stop in your statement projects such meaning.

3. It can cause the unexpected.
Examples
i. Give me my pen's cover.
ii. Give me my *pen!s cover.

Can you see what the wrong use of a punctuation mark, precisely the exclamation mark (!), almost caused in example two? I will let you ponder on that, but don't take too much time. Lol!

There are two basic types of punctuation marks:
a. The terminal punctuation marks
b. The internal punctuation marks

The terminal marks (the full stop, question mark and exclamation mark) are used at the end of sentences. These are the strongest punctuation marks and are used primarily to indicate the end of a sentence.

On the other hand, the internal punctuation marks are used within sentences. Internal punctuation marks comprise the comma (,), semicolon (;), colon (:), parenthesis (), apostrophe ('), dash (–), caret (ʌ), quotation mark/inverted comma (" ") or (' '), hyphen (-) and suspension point (...).

Each of these punctuation marks is used to achieve different communicative purposes when using the English language. But this article only discusses the uses of the semicolon and its cousin, the colon.

SEMICOLON
Semicolon is one of the trickiest signs to use for writers, which is why you will find its usage the least. However, if properly used, it can be one of the most useful and significant punctuation marks.

The semicolon ( ; ) is basically a punctuation mark that indicates a more pronounced pause than that indicated by a comma but less important than that of a full stop. In other words, it is a longer pause than the comma but a shorter pause than the full stop.

USES OF THE SEMICOLON (;)

1. To separate main clauses which are are closely related and not joined with conjunction.
Example:
Writing is an acquired skill; it has to be learned.

"Writing is an acquired skill" and "It has to be learned" are two main clauses. A main or an independent clause is a simple sentence that can stand independently and still make a complete sense. It does not need another clause to be meaningful.

2. It is used between two independent clauses that are connected by conjunctive adverbs or transitional phrases (however, so, consequently, namely, therefore, as a result etc.).
Example
i. I love the English Language; however, I hate its complexities.

ii. Traditional values still have a place in our society; therefore, they will never lose relevance. 

3. You can use a semicolon before a coordinating conjunction to separate items in a list where one or more of the items contain(s) commas or other punctuation(s).

Example:
This article discusses punctuation under three broad headings: the meaning of punctuation, which reviews the concept of punctuation (by different scholars); how it is used; its implications; and how it can be applied.

4. A semicolon is used to separate the series of loosely related clauses.
Examples: 
i. Her court was pure; her life serene. 

ii. God gave her peace; her land reposed. 

COLON
Unlike the semicolon, the colon (:) is a punctuation mark that is used to precede a list of items, a quotation or an expansion or explanation. While a semicolon links two independent statements, this punctuation mark flows conveniently from the first statement to the second. Usually, it links a general or introductory statement to an example, or a cause to an effect or a premise with a conclusion. This shall come to fore as we illustrate some of its uses.

USES OF COLON (:)
1. The most common use of the colon is to indicate to the reader that a list of items follows. In this case, it is used before listing the items.

Example:
All corps members were told to bring the following items for the orientation course: a torch, a waist bag, two sets of night clothes, a pair of white snickers, underwear etc.

2. It is used sometimes to indicate more emphasis in indirect speech.
Example:
The little girl screamed: “Help! Help! I'm dying!" 

3. It is used to divide the title of a book from the subtitle.
Example:
Stylistics: Theory and Practice

4. It is used to make a difference between the hours and minutes when writing the time.
Example:
The time is: 04:00 PM

5. It is used in differentiating the chapter and verse in the Bible.
Example:
Genesis 1: 3

6. It is used to introduce a quotation.
Example
Tammy says: “The patient dog no longer eats the fattest bone." 

7. It is used between sentences that are grammatically independent but closely connected in sense.
Example:
Study to acquire the habit of thinking: No study is more important. 

In sum, since punctuation marks are capable of altering the actual meanings of sentences, it is very important for language users to use them correctly and when necessary. This will also make their writings sophisticated.