Twelve teenagers of Puerto Rican origin were interviewed to determine their proficiency in speaking and understanding Spanish. Three levels of oral Spanish proficiency were established as reference points on a continuum by using self-ratings, peer-ratings, and self-reports of usage. These impressions were verified by the number and type of errors made by each group, the number and type of verb forms correctly used, and the use of English. The study exposed the following general characteristics of the teenagers' Spanish: (1) comprehension exceeded expressive ability; (2) the verb system showed a great deal of variation, but there were no attempts to simplify it in a pidginization process; (3) the present perfect tense was not used; (4) the use of the subjunctive varied with the fluency of the speaker; and (5) the interviewer was not addressed with the third person singular. Fifteen adult Spanish speakers judged the acceptability of sentences transcribed from the interview. Unacceptable practices included English syntax and vocabulary, verbs incorrect for person or number, indicative used for subjunctive, and present or subjunctive used for conditional. (Author/JB)