I from Honduras.
Es correcto por que estamos hablando de 2 clases, y estamos usando un adjetivo cuantitativo que modifica al sustantivo que describe convirtiendolo asi en plural, y en este caso colcoamos CLASSES
Si fuera una clase seria CLASS
It is correct because we are talking about 2 classes, and we are using a quantitative adjective that modifies the noun it describes turning it into a plural form, and in this case we place CLASSES
The reason why it should be “two classes on Tuesday” is because that would be translating the text directly. It says “dos clases el martes” the word “el” in this sentence is translating as “on” and if you take that out, then you just took out one of the words it wanted you to translate
Yep and they mean different things in different languages, at least in some contexts.
For instance, Spanish uses "en" which means "in" in places where English would use "on" or "at" such as "en vienes" "on Friday" or "en universidad" "at University".
So as they are not a native English speaker, they didn't know which preposition was used in this exercise.