The /k/ sound has five spellings in English: C, K, CK, CH, and QU. Each follows a clear rule. Once you know them, you can predict pronunciation when you read a new word.
The Five Spellings
| Spelling | When to use | Example |
|---|---|---|
| C | before a, o, u, consonant | cat, cot, cut, cry |
| K | before e, i, y | key, kid, sky |
| CK | after short vowel at end | back, pick, lock |
| CH | Greek-origin words | chemistry, school |
| QU | followed by /w/ sound | quick, quiet |
Rule 1: Hard C — Before a, o, u, or a Consonant
C says /k/ before a, o, u or another consonant.
Rule 2: K — Before e, i, y
Use K instead of C before E, I, or Y, because C in those positions would say /s/.
Rule 3: CK — After a Short Vowel at the End
At the end of a one-syllable word, after a short vowel, use CK. After a long vowel or another consonant, use K alone (book, milk, talk).
Rule 4: CH — Greek-Origin Words
CH usually says /tʃ/ (church). But in Greek-origin words it says /k/ (chemistry, school, ache, character).
Rule 5: QU — Almost Always /kw/
QU = /kw/. Q is almost always followed by U. Exception: French-origin words like plaque, antique, unique use QU = /k/.
Quick Test
- __ar (vehicle) → C (before a)
- __ettle (for boiling water) → K (before e)
- roc__ (large stone) → CK (after short o)
- __oir (singing group) → CH (Greek)
- __een (royal woman) → QU