Complex sentence: Hill noted the disconnect between this linguistic behavior and the social climate of monolingual language policy and education and anti-immigrant sentiment and concluded that Mock Spanish, though seemingly benign, is used to "index and reproduce deep prejudices against Mexicans and Spanish speakers".
Split into simpler sentences: Hill noted the disconnect between this linguistic behavior and the social climate of monolingual language policy and education and anti-immigrant sentiment. She concluded that Mock Spanish, though seemingly benign, is used to "index and reproduce deep prejudices against Mexicans and Spanish speakers".