Irene E. Schoenberg has taught ESL for over twenty-five years at Hunter College's International English Language Institute and for eighteen years at Columbia University's American Language Program. She has trained ESL and EFL teachers at the Columbia University's Teacher's College and the New School for Social Research. She has lectured at conferences, English language schools and universities in Brazil, Dubai, El Salvador, Guatemala, Japan, Mexico, Nicaragua, Taiwan, Thailand, and the United States. She is the author of Talk about Trivia; Talk about Values; Focus on Grammar: A Basic Course for Reference and Practice; and the co-author with Jay Maurer of the True Colors series. Ms. Schoenberg holds an MA in TESOL from Columbia University. Focus on Grammar: An Introductory Course for Reference and Practice has grown out of the author's experience as a practicing teacher of English.

Jay Maurer has taught English in binational centers, colleges, and universities in Portugal, Spain, Mexico, the Somali Republic, and the United States. In addition, he taught intensive English at Columbia University's American Language Program. He was also a teacher of college composition, literature, speech, and drama for sixteen years at Santa Fe Community College and Northern New Mexico Community College. He is the co-author of the three-level Structure Practice in Context series; co-author with Irene Schoenberg of the five-level True Colors series; co-author of the True Voices video series; and author of Focus on Grammar: An Advanced Course for Reference and Practice, First and Second Editions, and CD-ROM. Currently he writes and teaches in Seattle, Washington.