Prediction is one of the techniques that have been applied to Augmentative and Alternative Communication to help people enhancing the quality and quantity of the composed text in a time unit. Most of the literature has been focused in word prediction methods that may be easily applied to non-inflected languages. However, for inflected languages other approaches that mainly distinguish roots and suffixes may enhance the results (in terms of keystroke savings and hit ratio) of predictive systems. In this paper we present the approaches we have applied to the Basque language (an inflected one) and the results they achieve with a particular text (that was not used while creating the initial lexicons the systems use for prediction). Starting from this evaluation, one of the presented approaches is suggested as the best one.