Mismo sonido para: ca = ka ce = se = ze ci = si =zi co = ko cu = ku que = ke qui = ki

Not usually, ci sounds like "th".. always (In the Castillian Spanish). But, it's true than "ci" could sound "si" in the accent of many people who speak Spanish... in the south of Spain and in the most places of South America. (Perhaps 90% of Spanish speakers...) Is "seseo": to speak with "s" instead of "z". (Please, correct my English...if you want)

Juan Carlos' answer was fine--In the Spanish accent from Spain (Castilian-Spanish), the combination 'ci' usually is pronounced with a ' Th ' sound. For example, el cine (el thee-ney) the cinema, cinco (theenKo) five, el circo (el theerKo) the circus.

wow, Thank you. I understand now!

It,s easy....for a spanish native. ;-) The "c" sounds /k/ with the letters "a", "o", "u" "Casa, comida, cuchara" and sounds /z/ with "e" and "i" . "cerveza, cielo." The sound /z/ is written"z" with a, o, u : zapato, zoquete, zumo. /K/ is written "qu" with e and i . "querer, quiero." The letter "k" is unusually in spanish, onli for words (foreigners?) like "kiwi, kart, kimono.."