Textbook is one of the basic tools for someone to learn a foreign language. When there are typos in a beginning-intermediate level Chinese textbook, usually students would assume they are “correct” and move on.
I wonder how the editors of “Ultimate Mandarin Chinese” would feel after reading this post, especially when the slogan on its cover says “The Most Complete and Up-to-Date Program Available”.
How about recheck your book with a dictionary?
人 = person
入 = enter
