Semicolons are stronger than commas, but weaker than
periods. The semicolon’s main job is to separate things. Semicolons sometimes
serve as a replacement for commas (see # 4 below). The following are different situations
where a semicolon should be used:
1.
To separate two independent clauses that are very closely related.
For example:
Jean rappelled down the mountain
as fast as she could; her friends cheered her on from below.
Here, the two independent clauses are
closely related because they are describing the same scene. Therefore, a
semicolon is used.
2.
To separate two independent clauses with the aid of a conjunctive adverb
and a comma.
For example:
The recue team was large and
highly trained; therefore, the mine workers were rescued fast.
In the above sentence, “therefore”
serves as the conjunctive adverb. It is providing a transition between the two
independent clauses. Conjunctive adverbs need a semicolon in front of them and
a comma after them. The semicolon is used here with the conjunctive adverb and
the comma.
3.
To separate an independent clause from an introductory word or phrase
that introduces a list (some examples of such words and phrases are: such as,
for example, for instance, therefore, however, namely).
This list can either be by itself
or part of another independent clause.
For example:
Many people bring too many extra
things on their vacations; for instance, plants, chairs, trophies, and candles.
Here, the first independent clause
is followed by the introductory phrase “for instance”. In this case, the
introductory phrase introduces a list. A semicolon is used to separate the
independent clause from the introductory phrase.
The list introduced by the introductory word or phrase
can also be part of an independent clause.
Consider the following sentence:
You should bring as few items as
possible on the campout; therefore, plants, big tents, chairs, and candles
should not be packed for the trip.
Here, the first independent clause
is followed by the introductory word “therefore”. The introductory word
introduces a list. This time, the list is part of a second independent clause.
A semicolon is used to separate the first independent clause from the
introductory word that leads up to the second independent clause.
4.
To separate items in a list that already have commas within them.
Consider the following sentence:
Jeffery traveled to Destin,
Florida; Springfield, Illinois; Houston, Texas; Flagstaff, Arizona; and
Sacramento, California on his business trip.
In the above sentence, the items in
the list are cities and their respective states; they already have commas
within them. Therefore, semicolons need to be used to separate the items.
Otherwise, the list would be very confusing. In this case, a semicolon is
serving as a replacement for a comma.
5.
Semicolons can also separate long items in a list or long independent
clauses.
For example:
The fact that Jerry had known
Marie for 15 years and had never been told that she was a secret agent made him
angry; but she apologized to him after they met again.
Here, the first independent clause
is very long, so a semicolon separates the two independent clauses.