Formative feedback can provide information about how learners develop their competences in a knowledge domain. This information can determine learners’ progress and is essential in suggesting remedial actions which overcome gaps in knowledge. Finding this information, however, is a time consuming task. This paper elaborates the theoretical background of conceptual development, and argues that it can be (semi) automatically diagnosed using Language Technologies. It also presents, as future work, a description of a pilot that will be conducted to explore how existing tools that automatically generate concept maps, can be used to diagnose learner’s conceptual development.