Fleas in the mouth
Fleas in the mouth, a Chinese idiom, Pinyin K ǒ UZH ō ngz ǎ OSH ī, refers to the enemy who is easy to eliminate, just like the fleas in the mouth. So it is also called "lice in the mouth".
Pinyin
kǒuzhōngzǎoshī
explain
It refers to the enemy who is easy to destroy, just like the louse in the mouth. So it is also called "lice in the mouth". 
Classics
In Han Feizi's Qishu, when Wang was near Dongyang, there were lice in the mouth of Han Zhang. Biography of Wang Mang in the history of Han Dynasty: Han Weijin, the captain of the school, said: "swallow the Hu Lu with the power of the new room, and there are no fleas and lice in the strange mouth."
Discrimination
Synonym: louse in the mouth usage: as the subject and object; refers to the enemy easy to destroy.
Fleas in the mouth
Set down the capital to support the dangerous - dìng qīng fú wēi
lay down one 's life for justice - shì shēng qǔ yì
Fish letters and wild geese letters - yú shū yàn xìn