1 complete change from the normal state (idiom); quite uncharacteristic
2 entirely outside the norm
3 out of character
三纲五常
sān gāng wǔ cháng
1 three principles and five virtues (idiom)
2 the three rules (ruler guides subject, father guides son and husband guides wife) and five constant virtues of Confucianism (benevolence 仁, righteousness 義|义, propriety 禮|礼, wisdom 智 and fidelity 信)
人之常情
rén zhī cháng qíng
1 human nature (idiom)
2 a behavior that is only natural
兵家常事
bīng jiā cháng shì
1 commonplace in military operations (idiom)
千里马常有，而伯乐不常有
qiān lǐ mǎ cháng yǒu , ér Bó Lè bù cháng yǒu
1 lit. there are many swift horses, but very few who can spot them (idiom)
2 fig. many have talent, but few can recognize talent when they see it
法轮常转
Fǎ lún cháng zhuàn
1 the Wheel turns constantly (idiom); Buddhist teaching will overcome everything
知足常乐
zhī zú cháng lè
1 satisfied with what one has (idiom)
祸福无常
huò fú wú cháng
1 disaster and happiness do not follow rules (idiom); future blessings and misfortunes are unpredictable
老生常谈
lǎo shēng cháng tán
1 an old observation (idiom)
2 a truism
3 banal comments
虚与委蛇
xū yǔ wēi yí
1 to feign civility (idiom)
蹈常袭故
dǎo cháng xí gù
1 follow the same old path (idiom); stuck in a rut
2 always the same routine
进退有常
jìn tuì yǒu cháng
1 to advance or retreat, each has its rules (idiom from Zhuangzi); many translations are possible