play favorites 偏心，偏爱

　　Teachers are not supposed to play favorites. That's unfair to other students.

　　老师不应该有偏心，这样对其他学生不公平。

　　It's ok to have a good friend in the office, but don't play favorites.

　　在办公室有一个朋友是好事，但也不要太偏心了。

　　疯狂练习吧！