have known each other long
Xiangzhiyousu, a Chinese idiom, Pinyin is Xi āī y ǒ us ù, which means a good friend who knows each other all the time. From the popular romance of the Republic of China.
The origin of Idioms
Chapter 46 of the popular romance of the Republic of China written by Cai Dongfan and Xu Xun's father: "it's unnecessary for others to talk about it. It's Duan Zhiquan and others who have been with the president for many years and know each other well. Today, they are also suspicious."
Idiom usage
A good friend who has always known each other.
Examples
It's not necessary for others to say that even Duan Zhiquan and others have been with the president for many years, and today they are suspicious. (Chapter 46 of the popular romance of the Republic of China by Cai Dongfan and Xu Xianfu)
have known each other long
distant relatives and next-door neighbors - yuǎn qīn jìn lín
lively and vigorous flourishes in calligraphy - lóng pán fèng zhù
all one can see is grief -- full of grief everywhere - mǎn mù qī liáng