CHAPTER 5. Writing skills 83 (2012) showed, the implicit learners seem to take longer to internalize the more subtle morphosyntactic patterns. Of course, the current study has its limitations. Empirical studies usually require full experimental control to allow generalization of ndings, but classroom research requires high ecological validity to support teaching practice. Moreover, if this type of classroom research is widely replicated, as advocated by DeKeyser and Botano (2019), this lack of methodological rigor will be compensated as results will become more robust and more relevant for practitioners. is study also has several strengths: First, although results were only obtained at one point in time (a er six years) and development of writing skills cannot be determined over time, its duration was necessary to facilitate a comparison of two teaching programs which di er with regard to the degree of implicitness. Second, this study has a high ecological validity with participants who are not just learning for the sake of the experiment (DeKeyser, 2003), and French as a FL. As the majority of the experiments in this eld so far have been conducted with English as a FL, it is important to conduct experiments with other languages as well, especially those where extramural exposure is limited. Indeed, in most existing e ect studies on English, there is generally no control over informal learning at home, which makes French in the Netherlands an excellent choice for such a study as there is almost no extramural exposure normally. Despite these strengths, the ndings of this explorative study should be interpreted with caution and more long-term and ecologically valid studies are needed to con rm the ndings. e current long-term classroom study suggests that general learning mechanisms like statistical learning are capable of facilitating FL acquisition through FL exposure and active use, if given su cient time. It seems that a predominantly implicit, DUB FL teaching program might be as e ective as a predominantly explicit, SB approach in terms of achieving morphological accuracy and even more e ective in achieving complexity and uency. As previous studies have speculated that uency especially may be related to the use of chunks, the next chapter will explore if chunk coverage can be related to either complexity or uency and whether it should be regarded as a sub-construct or an independent one.