WHEN PULITZER PRIZE–WINNING AUTHOR Junot Díaz spoke to a group of first-year college students in California in 2008, he used colloquial English and Spanish, plus a few four-letter words—and the students loved every minute of it. When he was interviewed a month later on National Public Radio, however, Díaz addressed his nationwide audience in more formal standard English. As a college student, you will be called on to think carefully about how to make appropriate choices. Since standard academic English is still the expected variety of English for most if not all your writing for your classes, you will want to use it effectively. But you may also choose to use another language or another variety of English for rhetorical purpose or special effect. Strong writers recognize these differences and learn to use all their languages and language varieties in the most appropriate and powerful ways.