In terms of phonology, what do "ch" and "sh" share in terms on natural class?

Question

sorry but please state you source...

Answer 1

"ch", as in "chair":
1. voiceless (no vibration of the vocal cords)
2. point of articulation: alveopalatal
3. manner of articulation: affricate

"sh", as in "share":
1. voiceless
2. point of articulation:alveopalatal
3. manner of articulation: fricative

As you can see, those two consonants have the following in common: (A) both are voiceless and (B) both are alveopalatal.

Alveopalatal consonants: the flow of air is stopped by creating a block between the tongue and the hard palate just behind the alveolar ridge.

Answer 2

Are you an English major?If you are, it is best if you read the works of Chomsky, Ladefoged and other prominent phonologists. They use varying terms that basically describe the same concepts. But if you're not and you just want to get a broad overview of what a natural class is, I suggest you get Introduction to Language by Hyams,Fromkin, (and another author whose name i can't remember) and read on the phonology chapter. it's a pretty good introductory book and it includes chapters on phonetics,syntax,morphology,etc.=)

Answer 3

They are both voiceless and palatal but "sh" is a fricative while "ch" is an affricate. I don't know what the final terms mean but the others are common sense (voiceless=without use of vocal chords, palatal=using hard palate).

See the attached link.