This article reports one aspect of a project concerned with form-class effects of nouns, lexical verbs, and adjectives in the written production of university-level Swedish learners of English as a foreign language. The main reserach question driving the project concerns the proneness to lexical error in the foreign language of these three parts-of-speech: nouns, lexical verbs, and adjectives. This article reports the results of a subsidiary research question which concerns task-type effects for lexical errors, i.e. it investigates the distribution and types of lexical errors in two different production tasks: free composition and translation of a slightly modified newspaper text from Swedish (L1) into English (L2).