21b Consider separating the clauses with a semicolon, a colon, or a dash.

When the independent clauses are closely related and their relation is clear without a coordinating conjunction, inserting a semicolon is one method of revision. (See 32a.)

The example reads,

Tragedy depicts the individual confronted with the fact of death (strikethrough) comma (end strikethrough) (insert) semicolon (end insert) comedy depicts the adaptability of human nature.

A semicolon is required between independent clauses that have been linked with a transitional expression such as however, therefore, moreover, in fact, or for example. For a longer list, see 32b.

The example reads,

In her film adaptation, the director changed key details of the plot (strikethrough) comma (end strikethrough) (insert) semicolon (end insert) in fact, she added new scenes that do not appear in the novel.

A colon or a dash may be more appropriate if the first independent clause introduces the second or if the second clause summarizes or explains the first. (See 32e and 36a.) In formal writing, the colon is usually preferred to the dash.

Inserting a colon is an appropriate method of revision if the first independent clause introduces a quoted sentence.

The example reads,

Nobel Peace Prize winner Al Gore had this to say about climate change (strikethrough) period (end strikethrough) (insert) colon (end insert) ‘The truth is that our circumstances are not only new; they are completely different than they have ever been in all of human history.’