Sparrow: Sparrow.
There is an idiom "Yan knows the swan's ambition", which comes from Historical Records Chen She Family: "Hey, Yan knows the swan's ambition?"
original text
When Chen She was young, he tried to plow with people's servants, but he was disappointed for a long time. He said, "Gou calligraphy" swallows know the ambition of swans. "
Don't forget each other. The servant smiled and replied, "If you plow for your servant, how can you be rich?" "Chen She sighed and said," alas, sparrows know the ambition of swans! "Source: Historical Records Volume 36:" Whew, do sparrows know the ambition of a swan? "
translate
When Chen She was young, he was hired to farm with others. (One day) Chen She stopped farming and went to the highland near the field (rest). He sighed indignantly for a long time because of disappointment and said, "If (one day) we are rich, don't forget our old friends." The employees smiled and replied, "You are a hired farmer. Where did you get the money?" Chen She sighed and said, "Alas, how can a sparrow know the ambition of a swan!" "
"Swallows know the ambition of swans" to the effect that:
Interpretation: How can a sparrow know the great ambition of a swan?
Metaphor: Where do ordinary people know the hero's ambition?
Swallow made a grand plan: different contexts have different meanings.
1. Swallows can also aspire, and finches can also have big ambitions. To make a metaphor, it is unrealistic to pursue too high and too far goals.