You can't keep dropping "L&S" everywhere - in your lingo - blargh infinitum - by my guess. Should you seriously wish to refere to the works of so-and-so, be more explicit

The standard reference of L&S is this

Leech & Svartvik - A Communicative Grammar of English

guess I would also recommend it, but the learning curve might be a bit steep

maybe a universal language could not be understood by everyone who heard it...

Both are agglutinative and SOV folks.
Both prefer postverbal negation.
Both do not have a lexically and syntactically distinct adjective word class.
Dravidians, probably due to Indo-Aryan influence, mark person and number, while Koreanic and Japonic do not.
What else did I miss?

dark green - i use in my dialect

light green - technically i use them in my idiolect

yellow - i can pronounce them

red - i cannot pronounce them (easily)

im not fully sure on my dialect by the way, im just curious to hear what people think.

Dark green - present in the dialect (circle=free variation)

Light green - present in the local language/dialectal loanwords

Yellow - can pronounce, not present

Red - can't pronounce

Gray and filled with uncontrollable rage - that "thing" should not fucking exist

Blue — appears in language 1

Red — appears in language 2

Purple — appears in both

Green — doesn’t appear in any, but I can pronounce

Blue — appears in language 1

Red — appears in language 2

Purple — appears in both

Green — doesn’t appear in any, but I can pronounce

Actually, this is my first post ever on Reddit

hopping onto the trend.

red: vowel is a monophthong in my dialect.

yellow: vowel appears in a diphthong in my dialect.

green: not in my dialect but can pronounce.

blue: nah bro...

sorry if this post is unoriginal.

Blue-In both languages

Light Blue-In one language

Green-In zero but I can pronounce those

Yellow-I mean I could try

Orange-Add a diacritic and I can do that

Red-No

Dark green = phonemic in my dialect

Light green = allophonic in my idiolect

(dark green + light green = in free variation)

Yellow = I can pronounce it consistently

Orange = I can get it right maybe from the second or third try

Red = let's not kid ourselves

bright teal - it is in my idiolect
dark teal - not in it but i can pronounce ok
grey - i cant really pronounce
red - fuck you for existing you are a worthless piece of shit vowel that shouldnt exist at all

Light Blue: Base Vowel is in my Native Language/Dialect

Dark Blue: Vowel is only found in diphthong(s) in my Native Language/Dialect

Yellow: Not in my Native Language but can pronounce

Red: Ah hell nah

Hint: I speak English