1. I have two dance classes on Monday.
2. I have two dancing classes on Monday.
(which one is correct as a subject, dance or dancing?)
dancing is an action verb not an adjective. Dance could be a noun or adjective depending what is used, so the first one is correct since its describing classes.
Anonymous is incorrect. When you use 'dancing,' the present participle of the verb, it can serve as an adjective.
In your sentences, 'dance' and 'dancing' are being used as adjectives to describe 'class,' not as subjects.
Both your sentences are correct, but the phrasing most commonly used is sentence 1.
Dance classes is the correct one
Both sentences can be grammatically correct, but there is a slight difference in meaning.
1. "I have two dance classes on Monday."
In this sentence, "dance" is used as a noun. It refers to the activity or style of dance classes you have on Monday. For example, you might have a ballet class and a hip-hop class on Mondays.
2. "I have two dancing classes on Monday."
In this sentence, "dancing" is used as a gerund, which means it functions as a verb acting as a noun. It refers to the action or act of dancing that takes place in the classes. For example, you might have two classes where you actively participate in dancing.
Both "dance classes" and "dancing classes" are acceptable phrases, but their usage depends on the intended meaning and context.