Duck soup may taste as good as chicken soup, but it really is better known as an expression. Duck soup is an activity that is extremely easy, that involves no effort. To a farmer, milking a cow is "dock soup". But milking is not "duck soup" to someone from the city.
　　Some experts say the expression is not very old. And they say it probably is based on an earlier expression, "sitting duck". A duck that is resting on the water is much easier to shoot than a duck that is flying in the air. So, a sitting duck is much more likely to be shot and end up in the soup pot--the makings of duck soup.
　　People use the expression "sitting duck" to describe someone or something that is an easy target or open to attack. An elected offical who does nothing for the voters is a sitting duck in the next election.
　　
　　鸭汤也许跟鸡汤一样好吃，但是在英语中，它作为词语更为人知。它指某种特别容易、不费吹灰之力的事。对农民来说，挤牛奶可以说跟喝“鸭汤”一般容易；对城里人来说，可就是两码事了。
　　有些专家说，这个用法的历史并不长。据他们看，“鸭汤”也许来源于另一个更古老的说法：“坐鸭”。浮在水面上歇息的野鸭子，自然要比空中飞的容易打得多了。因此，“坐鸭”往往就会被射中，放进汤锅里做成鸭汤了。
　　于是，人们用“坐鸭”来形容好打的目标或容易攻击的人。一位民选官员如果不为选民办事，到了下次选举时就会成为一只“坐鸭”。