n.(鸭子)嘎嘎叫声；庸医；冒充内行的人
v.嘎嘎地叫；大声闲谈；冒充内行
adj.骗人的
A duck's quack doesn't echo and no one knows the reason. 鸭子呱呱叫是不会产生回音的
She discovered that the man was a quack. 她发现那人是个庸医。
The quack was stormed with questions. 江湖骗子受到了猛烈的质问。
用作形容词 (adj.)He was told that it's a quack medicine. 他被告知这是假药。
n.骗人的治疗；大吹牛；骗子的行为
n.密医；庸医；骗子
