zài / shù xué kè / shàng / lǎo shī / jiāo / wǒ men / yòng / fù shù píng miàn / lái / biǎo shì / xū shù在数学课上,老师教我们用复数平面来表示虚数。In math class, the teacher taught us to use the complex plane to represent imaginary numbers.