Day 108: Use square brackets to insert comments into quotes.

Let’s say you are quoting your department supervisor in a letter to customers. The reader may not know the meaning of a particular word the supervisor used, so you want to include a definition. However, the definition is not part of the quote. You use square brackets to indicate that you are inserting words that are not part of the quote. These are square brackets, a.k.a. braces: [ ]. Consider this sentence.

“The consumer reactualizes the initial subscription fee.”

What does the speaker mean by “reactualizes”? We can provide that information in this way:

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“The consumer reactualizes [repays] the initial subscription fee.”

Any time you want to interject text into a quote, use square brackets to let the reader know that the words you included are not part of the quote but are your own words.