The '
c', when followed by 'e' or 'i' and the '
z', no matter the vowel that follows it, are pronounced like the 'th' in the English word 'thin' (IPA:
/θ/) (not like the 'th' in the English word 'the' (IPA:
/ð/)). This pronunciation is only found in peninsular Spanish (the Castilian spoken in Spain).
In Latin America, these two consonants are pronounced like an '
s', when followed by a vowel.
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Only two languages of Spain, Castilian and Galician, have this sound and use the same two letters to represent it.