The students were ________ over the ________ problem，listening to the teacher with a ________ expression on their faces.
A.puzzled；puzzling；puzzling
B.puzzled；puzzling；puzzled
C.puzzling；puzzling；puzzled
D.puzzling；puzzled；puzzling
网友回答
B解析形容词辨析。Puzzled感到困惑的,通常形容人；puzzling令人困惑的，通常形容事物；expression表情，它与人有关，所以仍然用puzzled修饰。句意：带着困惑的表情听老师讲课，学生们对于那个令人困惑的问题感觉很困惑。