Signal phrases are short phrases that introduce a quote, paraphrase, or summary; they signal to readers that an outside source is being used.
A signal phrase introducing a quote:
The CEO of Lighthouse Consulting predicts “a year of exciting, challenging endeavors that will expand the company’s horizons and stimulate growth throughout the company.”
A signal phrase introducing a paraphrase:
New York Times columnist Ashley Green reports that the city’s carbon dioxide emission rate of 60 million metrics a year could be cut by 35% if roads were redesigned to accommodate bikers.
A signal phrase introducing a summary:
The nutritionists Young and Robinson propose that an iron-fortified soy sauce is the solution to the anemia problem in the young women of rural China.
Why do we use them?
There are three important reasons to use signal phrases:
To mark boundaries: Signal phrases mark boundaries between your words and the source’s words. By marking the boundaries, you also provide a smooth transition for the reader between your words and the source.
To emphasize the source: Signal phrases call attention to the author or source being used. In some cases, such as a literature review or the use of a well-known author, specific information about the source is important for the reader to know.
To avoid plagiarism: All source material must be cited, and signal phrases are one way to cite a source—however, additional citation formatting may be necessary depending on your citation style.
How can I use them?
Below are some guidelines and tips for using signal phrases.
Signal phrases usually include the author’s name but can also include the author’s job title or background (“reporter for Washington Post,” “researcher,” “senator,” “scholar,” and so on) and/or the title of the source.
Signal phrases usually come at the beginning of a sentence before the source material, but they can also occur in the middle of a source or at the end.
To avoid monotony and repetition, try to vary both the language and placement of your signal phrases.
According to Maxwell & Hanson, Some scholars have shown... In the words of researchers Smith and Johnson, “...” As legal scholar Terrence Roberts has noted, “....” “...,” attorney Smith claims. Smith and Robert offer a persuasive argument: “....”
Choose a verb that is appropriate to the way you are using your source. Below is a list of verbs that can be used in signal phrases:
acknowledges adds admits affirms agrees answers argues asserts claims comments concedes confirms contends counters counterattacks declares defines denies disputes echoes endorses estimates finds grants illustrates implies insists mentions notes observes predicts proposes reasons recognizes recommends refutes rejects reports responds reveals speculates states suggests surmises warns writes
Adapted from A Writer’s Reference with Writing in the Disciplines 7th ed. by Diana Hacker and Nancy Sommers