If readers are unlikely to be familiar with a word, a phrase, or an idea important to your topic, you must explain it for them. Quoting or paraphrasing a source can help you define terms and concepts in neutral, accessible language.

The Civil War practice of giving no quarter to an enemy—in other words, “denying [an enemy] the right of survival”—defied Lincoln’s mandate for humane and merciful treatment of prisoners.⁹