Every time the old man talks about his theory that "there's no point in studying," Mrs. Chang, not able to challenge him face to face, waits until he retires to his room and then immediately comes up with a way to "disinfect" the atmosphere so her son doesn't really become lazy in his studies.
每當老人家說起「讀書無用論」，張太太雖不會當面反駁，但回房間後立刻就會想辦法「消毒」，避免孩子因此懶散下來。