可以说 "The class is very quiet." 或 "Everyone in the class is very quiet."
来源：这句话的意思是指班级里的所有人都很安静，"class" 指的是学校里的一群学生，"quiet" 指的是不喧闹的、安静的。
英文例句及其中文翻译：
"It's so quiet in the pbrary. You could hear a pin drop." (图书馆里非常安静，你甚至能听到针掉落的声音。)
"She always keeps her voice down when she's in the office. She's very quiet." (她在办公室里总是小声说话。她很安静。)
"He's a quiet person. He doesn't pke to make a lot of noise." (他是个安静的人。他不喜欢制造太多的噪音。)
来源：这句话的意思是指班级里的所有人都很安静，"class" 指的是学校里的一群学生，"quiet" 指的是不喧闹的、安静的。
英文例句及其中文翻译：
"It's so quiet in the pbrary. You could hear a pin drop." (图书馆里非常安静，你甚至能听到针掉落的声音。)
"She always keeps her voice down when she's in the office. She's very quiet." (她在办公室里总是小声说话。她很安静。)
"He's a quiet person. He doesn't pke to make a lot of noise." (他是个安静的人。他不喜欢制造太多的噪音。)