This Research deals witl1 grammatical mistakes in translation English (as
source language [SL]) into bahasa Indonesia (as target language [TL]). The
investigation was in a text that consists of 301 sentences in both SL and TL.
Following Wills in Noss, (1982: 3) that stresses translation is a transfer process
which aims at the transformation of a written SL text into an optimally
equivalent TL text, and which requires the syntactic, the semantic and the
pragmatic understanding and analytical processing of the SL. Grammatical
mistakes belong to syntactic analytical processing and will influence the
semantic and pragmatic understandings. The investigation focused on the
preposition and determiner article (a/an) of the SL. The results of the
investigation that (1) There are two types of grammatical mistakes in the
‘ translating of the textbook, i.e. the mistakes in translating prepositions and die determiners (‘a’/’an’). There are 14 mistakes all together. (2) The dominant
mistake in the translating textbook are in translating determiner ‘a’/’an’, that
sometimes are translated and sometime are not.
