zài / xiàn / xìng / dài / shù / kè / shàng / lǎo / shī / yòng / jǔ / zhèn / shuō / míng / yāo / bìng / shǐ / de / xìng / zhì

在线性代数课上，老师用矩阵说明幺并矢的性质。

In linear algebra class, the teacher used matrices to explain the properties of an idemfactor.