Welcome to White Rabbit Japan!
Nihongo Tadoku Books Vol. 6 is the last volume in this series of graded readers. It features 4 stories aimed at intermediate and pre-advanced students at around the N2 level. At this level, the difference between a graded reader and a relatively easy to read book aimed at Japanese native speakers is minor. The language used in Vol. 6 is natural and feels like a real Japanese book rather than a graded reader. This book features level 4 and level 5 stories. It covers the grammar expressions explained down below.
potential form, imperative, passive, volitional, ～とき, から, たら・ば・なら, ～そう, ～よう, compound verbs
causative, causative passiv, ～そう, ～らしい, ～はず, ～もの, ～ようにする・なる, ことにする・なる