Indeed, using frequency alone will lead to a suboptimal set of sentences. Our approach was to choose sentences that increase smoothly in complexity, where we estimate complexity through a combination of criteria: frequency of vocab, tenses, number of clauses, etc.
Indeed, using frequency alone will lead to a suboptimal set of sentences. Our approach was to choose sentences that increase smoothly in complexity, where we estimate complexity through a combination of criteria: frequency of vocab, tenses, number of clauses, etc.