In English, the letters CH can make three sounds, but the two most common are /k/ (hard like cat) and /sh/ (soft like shoe). A third rare sound is /ch/ as in chair, but today we focus on the K and SH pronunciations.

CH sounds like /k/

This happens mostly in words borrowed from Greek. The rule: CH usually says /k/ in words with Greek roots, especially before A, O, U, or consonants.

Common examples:

CH sounds like /sh/

This comes from French influence. The rule: CH often says /sh/ in words borrowed from French, especially in the middle or end of words.

Common examples:

Quick Comparison Table

Sound	Origin	Common Position	Examples
/k/	Greek	Start or middle	chaos, echo, school, chemistry
/sh/	French	Middle or end	chef, machine, chic, parachute

Why Two Sounds

English borrowed heavily from both Greek (CH = /k/) and French (CH = /sh/). Over time, the spelling stayed the same even though the pronunciation changed depending on the word’s origin. The third sound /ch/ as in church or chair is the most common native English one, but the K and SH versions cause the most confusion for learners.

Spot the pattern next time you read. Greek root words lean toward /k/, French root words lean toward /sh/. This helps with spelling, pronunciation, and teaching phonics.