If you could provide more context, I might be able to help you figure out how to pronounce it. For example, tell me:
* Where did you see the word? (a book, a website, a conversation)
* What is the word supposed to mean?
Without more information, I can only offer a few possible pronunciations:
* Care-tel: Pronounced like "care" followed by "tell"
* Care-tahl: Pronounced like "care" followed by "tall"
However, these are just guesses. If you can give me more context, I can give you a more accurate pronunciation.