Practice in depth
It refers to honest heart and honest behavior.
Idioms and allusions
[source] Hanshu · biography of Han'an states: "he (Husui) is a gentleman in the deep."
Discrimination of words
As a predicate or attributive; used to be a person
Practice in depth
callosities found both on one 's hands and feet -- have been working hard - shǒu pián zú zhī
a happy event which pleases one 's mind -- a cheerful disposition and a happy event - shǎng xīn lè shì
hid work in the mountains and pass to like-minded people - cáng zhū míng shān