Have you ever wondered why scissors always ends with an 's'? My teacher used to tell me everything that has a pair in it is always plural. For instance, glasses, jeans, pants, etc. However, that is not always the case. I made some reading and found a clear understanding of the singularity and plurality of some nouns.
1. Cutting/Clipping Utensils
First, take a look at these items:
Scissors
Pliers
Forceps
Tongs
Tweezers
As you can see, all of these items have double sides thus we classify them as being always plural. Therefore, we cannot say 'a scissor' or 'there is a scissor'; it is always 'a pair of scissors' or 'there are scissors'. So if you wish to say more than one scissors, you still say 'there are many scissors'.
However, there are also tools that have two joined parts yet they are not always plural.
Bear Trap
Flat Iron
2. Eyewear
We do not say I'm wearing a glass but we say we wear glasses. Eyewears such as glasses, contact lenses, sunglasses, shades, goggles or even binoculars are ALL plural.
Rationally, we can relate this to the fact that these eyewears are made of two connected parts, resulting in the plurality.
3. Clothes
My curiosity of why we never use 'clothe' has always been unanswered. But I know clothes may refer to shirts, pants, jackets etc. so it should always be plural. However, certain types of clothings are strictly plural, even though it refers to a single unit. For instance:
Pants
Shorts
Jeans
Bell Bottoms
So all these clothings we wear with separate enclosures for our legs come in plural form. Other examples include leggings, tights, trousers, and skinnies. Even pyjamas (or pajamas in US English) is plural because it's a combination of a top and bottom.
4. Underwear
*sorry, no photos for this :P
As I've mentioned, clothes refer to a wide range of clothings. Underwear however, is singular. Yet, distinctively, those that come under underwear are mostly plural. For example, panties, boxers, drawers and briefs. Same concept here - the separate enclosures for our legs.
BUT why are thong/t-back singular? So is the bra (which has strong resemblance to goggles or glasses, no?)!
So yeah, English, as I've said, is funny and weird sometimes. But it's fun! Happy learning :)
Disclaimer: I do not label myself as an English expert but sharing also means learning. Nobody has perfect English but I believe learning knows no boundary. Feel free to correct me by commenting on my blog or Facebook posts/profile. I also welcome suggestions, ideas and any English-related info.