Harmony are agreeable features of classical music.

are not supposed to use in here because harmony is singular.
right or wrong??

harmony is an agreeable....

tnx

You are correct. The verb "are" should not be used in this sentence because the subject "harmony" is singular. The correct sentence would be: "Harmony is an agreeable feature of classical music."

You are correct. In this case, the word "harmony" is singular and refers to a single concept. Therefore, it would be more appropriate to use "is" instead of "are" in the given sentence. So the correct sentence would be:

"Harmony is an agreeable feature of classical music."