Numbers on a phone? OR Time?
In the English alphabet, the voiceless sounds are represented by the letters associated with the voiceless consonants: /p/, /t/, /k/, /f/, /s/, /ʃ/ (as in "sh"), and /θ/ (as in "th"). These sounds are produced without the vibration of the vocal cords. The corresponding letters are P, T, K, F, S, and combinations like "SH" and "TH."
The sound "h" is voiceless.
The legendary "roofcanini" is the only known voiceless plant, or subspecies of the albino black sheep.
The consonant "s" in the word "voice" is voiceless.
Constant Velocity
The Voiceless Message - 1911 was released on: USA: 29 November 1911
The cast of The Voiceless Songbird - 2010 includes: Mark Farag as Nameless
Voice of Voiceless - 2014 is rated/received certificates of: USA:PG (DVD rating)
Math uses letters to indicate that specific numbers are not known or as an abbreviation for certain constant.
If by permanent you mean constant, you cannot change something that is constant, therefore you cannot add to it (letters or otherwise). It has to be variable. Constant and variable are mutually exclusive terms.
There are 12 vowels and 18 consonants in the Tamil alphabet. Vowels can be short or long, and consonants can be classified into five groups based on their pronunciation. Additionally, there are special letters for voiced and voiceless consonants.
To identify if a word contains voiceless sounds, listen for the presence or absence of vocal cord vibrations when pronouncing the consonants. Voiceless sounds, like "p," "t," and "k," are produced without the vocal cords vibrating, while voiced sounds, such as "b," "d," and "g," involve vocal cord vibration. You can test this by placing your fingers on your throat while pronouncing the consonants; if you feel no vibration, the sound is voiceless. Additionally, checking a phonetic chart can help distinguish between voiced and voiceless consonants.