A reporting verb helps to make the distinction clear when someone is writing or talking about the words of another writer or speaker. Used to display verbatim quotes or to paraphrase, when judging or merely regurgitating, reporting verbs are common and needed components of every language. Dozens of words qualify in the English language, from "acknowledge" to "wonder," many with their own special tinges of meaning.
The most commonly used reporting verbs are the ones that merely transition to or from an exact quotation. These words can be "said," "stated," "reported" or even "restated." This type of reporting verb is judgment-free and usually a requirement of traditional journalism and academic writing or presentations.
Criticism leads to a more subtle form of reporting verb. Subtle implications can be made: "The author claims that Bigfoot is real," implies doubt. Conversely, "The experts conclude that the Earth is under attack," leaves little doubt, even though the new writer is emphasizing the expert's belief and not his or her own. Other evaluations can be made with words like "think," "propose," "believe" and the almost-cliche "allege." A person can "believe" he or she knows enough about reporting verbs at this point, but he or she would be wrong — an important distinction to be made.
A reporting verb used in an evaluative manner is not always criticizing another's words or thoughts. Some of these words are used to add emphasis — or even a lack of emphasis — where the original author intended it to be placed. This can be used emphatically, such as with verbs like "warn," "emphasize" or "stress." Using a reporting verb like "mention," by contrast, can help the writer indicate a subject's secondary importance. For example, "Did Mom mention whether it was okay for me to eat her leftovers?"
Reporting verbs are used to express many other sentiments in fresh content, from subtle doubt to outright disgust. "Dispute" or "refute" introduce these disagreements in objective terms. Others like "argue" can be more emphatic when the divisions are more contentious.
Many writers surmise that reporting verbs should be used sparingly. Others attempt to memorize as many as possible in order to capitalize on their subtle differences. Readers appreciate the effort to boltster understanding. They want to know whether a doctor "extols" a certain treatment or whether scientists are "forecasting" a dangerous change in the Earth's climate. The more complete a list of reporting verbs that a writer has learned, the more subtle tinkering he or she can do in writing.