1.in class是上课(比如说我们正在上课:We are in class.)
2.in the classroom是在教室内(比如说丽莉正在教室里看书:lily is reading in the classroom.)
in the classroom在教室里
in the class是在班上(比如说在班上我最高:I am the tallest in the class.)
1.在班上我最高:i am the tallest in the class
2.丽莉正在教室里看书:lily is reading in the classroom