Where are my glasses. Where are my pants. Where are my stockings. Where are my scissors. I think that in the distant past, these objects not joined as one, but English kept the plural form even after they were consolidated into one object.

Hi Xiao, how are you doing? Glasses - This word is considered a "pair" noun, meaning it's always considered plural, so, "are" is the correct verb form. Pair nouns are used to describe objects that are made up of two identical parts. Examples of pair nouns: glasses, jeans, pants, pyjamas, scissors. Keep up the great work!