Friendship, another concept which made you feel happy and fully.

友谊，是另一个会让你觉得幸福与充实的概念。

youdao

Another concept that's very basic here is covariance.

另一个基本的概念是协方差。

youdao

Another concept that's very basic here is covariance.

另一个基本的概念是协方差。

youdao