There is wide variability in the type and degree of bilingualism exhibited by persons from the various Spanish-speaking groups in the USA. Within particular subcultural groups, there is significant variability among individuals in the use of language patterns. An empirical study investigated the use of language pattern in specified social contexts among two generations in three distinct Spanish-speaking groups: New York Puerto Ricans, Central Texas Mexican-Americans, and Miami Cuban-Americans. A total of 295 families participated in the study. The Central Texas Mexican-Americans showed the greatest degree of displacement of Spanish by English as well as by "Spanglish," and the New York Puerto Ricans the greatest degree of "mother tongue" maintenance. Previous research suggests that language use are positively related. Contextual language use is an important factor which interacts with language learning and with academic achievement. It behooves teachers of persons from Spanish-speaking backgrounds to assess the language proficiency and the contextual use of language patterns of their students and to gear their curriculum accordingly. Contextual language use may be assessed by teachers through interviews and by behavioral observations, and the resulting data may be used to individualize instruction. (Author/CLK)