---

This is a descriptive case study which specifically examined the preposition acquisition differences and factors for those differences among Tanzanian EFL Learners.The study was guided by Interlanguage Theory by Larry Selinker. Systematic sample of sixty (60) University of Dar Es Salaam undergraduate students was involved in the study. The study was limited to EFL learners in higher learning institutions. The data were collected through questionnaire, preposition testing knowledge and documentary review. The data were qualitatively and quantitatively analysed. The findings revealed that the three preposition categories are acquired at different proficiency levels in which must be used prepositions are the first ones followed by obligatory deleted prepositions and finally optional prepositions. Furthermore, English medium students and mature entrants with English language experience were more advanced in acquisition of prepositions than their non-English medium counterparts. This books targets all students, academicians and other researchers who are interested in undertaking language acquisition related studies.

---

Issaya Lupogo is an Assistant Lecturer at Mzumbe University (Department of Education), he is coordinating language courses (Kiswahili and English) to undergraduate students. He is also involved in teaching, research and consultancy.He is a B.A (Education) and M.A (Linguistics) holder,from University of Dar Es salaam, Tanzania.

---