This chapter discusses the development of Finnish expressions of negation in four initially nonliterate women with very low oral skills during their first ten-month language course. While many studies have been published describing the learning of L2 Finnish by educated adult learners, hardly any research is available on how nonliterate adults learn Finnish. Yet research-based knowledge is needed for both pedagogical and resource-related decision making. The theoretical approach to additional language learning in this study is usage-based (e.g., Bybee 2008), with construction as the unit of analysis (Eskildsen 2012) and classroom as the interactional setting. In standard Finnish, the negative construction includes the negative auxiliary verb, inflected for person and number, and an uninflected lexical verb. In the data, verbs are present in only 23 percent of all the participants’ utterances. Unexpectedly, over half of these are , mostly formulated with just the negative auxiliary verb stem, with no personal endings and no lexical verb. A potential reason for this pattern is the low use of verbs in general and the inherent complexity of the Finnish negative construction. The simple negative verb stem ei is also sufficient for getting the message across. Individual differences exist in both the number and way of using the negative construction, indicating potential developmental paths. The development of the negative construction is compared with that of literate learners both in writing and in oral tests.