• In English the letter c is usually pronounced as a /k/ sound.
• We can also pronounce c as an /s/ sound.
• When c comes directly before the letters e, i or y we use the /s/ sound.
• In other cases we use a /k/ sound.
.
![When to pronounce the letter 'c' as k or s](https://www.edubloxtutor.com/wp-content/uploads/2021/06/Read-Spell-Level-33a-c-pronounced-as-k-or-s-1024x576.jpg)
Some words with both sounds:
bicycle
cycle
cybernetics
Exceptions:
soccer (we pronounce both the letters c as a single /k/ sound)
muscle.