Using signal or lead-in phrases is an excellent way to give your reader the necessary context to understand why you think the quotation is important to your discussion:
A signal phrase usually names the author of the source, gives the publication year in parentheses, and often provides some context. It commonly appears before the source material. To vary your sentence structure, you may decide to interrupt source material with a signal phrase or place the signal phrase after your paraphrase, summary, or direct quotation (A Canadian Writer's Reference (5th ed.), Hacker & Sommers, p. 453)
Example: Gore (1992) asserted the importance of considering the environmental effects of technological advances and noted that, “the appropriateness of a technology becomes increasingly important as its power grows and its potential for destroying the environment expands” (p. 146).
Verbs in signal phrases
Use active and descriptive verbs in your introduction of a quotation:
(Source: A Canadian Writer's Reference (5th ed.), Hacker & Sommers, p. 454)
For more information, please visit "Verbs for Referring to Sources" (University of Toronto). No matter how you choose to incorporate the idea into your text, you want to make it clear that you are referring to someone else’s idea, not claiming it as your own.
Deciding the appropriate verb tense usually comes down to using the one that best reflects the time period of the action described in the text.
Present or Past Tense in Signal Phrases
The choice of using present or past tense in signal phrases for paraphrases or quotations largely depends on the discipline in which authors are writing or the style guide they’re following.
According to APA Style, "the past tense is appropriate when expressing an action or a condition that occurred at a specific, definite time in the past, such as when discussing another researcher's work" (American Psychological Association [APA], 2020, p. 118). When expressing "a past action or condition that did not occur at a specific, definite time or to describe an action beginning in the past and continuing to the present", use the present perfect tense (e.g, Lee (2015) has used...).
Using the past tense to refer to other researcher's work reflects that the quotation or paraphrase presents the author’s thinking at the time of writing the text, which happened in the past. The published text may not reflect the author’s current thinking, so putting the signal phrase in present tense makes a claim that can’t be investigated within the source material. If you’re unsure of which tense to use in signal phrases, please check with your instructor, supervisor, or journal editor.
American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.). https://doi.org/10.1037/0000165-000
Adapted from "Using someone else's words: Quote, summarize, and paraphrase your way to success" © Center for Teaching and Faculty Development at San Francisco State University. Adapted with permission.