Part of a study is presented of native speakers of Hebrew who are acquiring English without formal instruction. A Hebrew-speaking child, aged 5 years 6 months, and her American playmate were audiotaped bi-weekly in natural settings for 11 months. The American child periodically used "foreigner talk," that is, the variety of language regarded as appropriate for addressing foreigners who are trying to learn the language of the host country. Monthly samples of this foreigner talk (FT) were excerpted from the transcripts. Given the longitudinal nature of such data, the following questions were chosen for study: (1) the prevalence and consistency of the American's FT; (2) the phonological and morphosyntactic features marking the FT; (3) the nature of the relationship between the FT and the Hebrew-speaker's emerging English; and (4) occasions when the American used FT. It was found that the presence of FT was relatively low and fairly constant and that the phonological and morphosyntactic features that comprise the FT behaved distinctly over time. As to the nature of the relationship between the American's FT and the foreigner's emerging English L2, the two systems change over time but independently of each other. A comparison of the results with data in other studies concludes the report. (AMH)