Student or Learner
Doesn't it have to be "sounds", a plural form?
1)Hangul has 8000 different kinds of sound and it is possible to write each sound.
I usually use the singular for the prepositional object, because the plural is handled by "types", kinds", "varieties", and "styles".
In my view. The prepositional object is the category.
Hence, "types of salad", "kinds of sound", "varieties of fruit", and "styles of car".
Others disagree, sometimes vehemently.
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