Speak high and speak low
The Chinese idiom, Pinyin is y á ng ā oy ǔ D ī, which means that you don't know the importance of your speech. From the Golden Phoenix hairpin.
The origin of Idioms
The third fold of Zheng Tingyu's jinfengchai in the Yuan Dynasty: "the shopkeeper says," sooner or later, the villain will speak high and speak low, and wait a little longer. "
Idiom usage
Used as a predicate or attributive; used in speech.
Speak high and speak low
change one 's name and surname - gǎi míng huàn xìng
go into the whys and wherefores of it - zhuī gēn jiū dǐ