The research presented in this paper aimed to serve two purposes. First, the objective was to understand the relationship between lexical and grammatical spelling. In this way, we studied how the frequency and consistency of verb interacted with the application of grammatical rules. Second, we investigated the dynamics of spelling during the writing of simple sentences to evaluate the impact of spelling one word on another; that is, to determine anticipatory and delayed spelling treatments in a sentence. Second- to fifth-grade students from primary schools completed a spelling-to-dictation task using sentences of the following type: Subject noun + Verb conjugated in the perfect tense + Object noun (e.g. "Mon frère a habité cette ville" [My brother lived in this city]). Verbs have been selected according to their lemma frequency and spelling consistency, while subject and object nouns were both frequent and consistent. Analyses of the proportions of errors on past participle inflections (N), subject nouns (N-1), and object nouns (N+1) showed an evolution of the impact of verb frequency or consistency during primary school. Depending on the position of the three types of words in the sentence and the grade of the writer, we noted classical or reversed effects of frequency or consistency. We discuss the results in light of statistical learning and Van Galen's cascading model of writing (Human Movement Sci 10(2-3):165-191, 1991).