The word "CHASA" is a bit tricky when it comes to spelling. In IPA phonetic transcription, it is spelled as /ˈtʃeɪsə/. The first sound, /tʃ/, is the "ch" sound in "chat". The second sound, /eɪ/, is the "ay" sound in "day". The third sound, /s/, is the "s" sound in "sit". Finally, the last sound, /ə/, is the schwa sound, which sounds like the "uh" sound in "sofa". So, the correct spelling of "CHASA" is indeed with a "CH" and not a "SH".