take a dancing class为什么要加ing

这里dancing是dance的ing形式，相当于形容词，用作定语，修饰后面的名词lesson。；

take a dancing class 上舞蹈课；

dancing class 舞蹈班;跳舞班

I would take part in a dancing training class, if there is an opportunity.

有机会的话会去参加一个舞蹈班。

Thought about the Dancing Class for Sports Correspondence Students

体育函授生舞蹈与健美操教学的思考

She went to Castle\'s dancing class every Friday.

她每个星期五去城堡的舞蹈课学跳舞。

I had dancing class today.

我今天上了舞蹈课。

I am considering dropping my dancing class.

我想退掉我的舞蹈课了。