'Doushite Umi no Mizu wa Shiokarai?' is a Japanese Graded Reader (JGR) designed for a proficiency level equivalent to Japanese Langauge Proficiency Test Level N5. The story utilizes a vocabulary of about 500 words. Graded readers in this series are written in easy and controlled language for foreign or second language learners of Japanese. Each of the pages features an audio track that you can listen to as you follow along with the text. When you have completed the story, you can review the vocabulary you have learned with interactive flashcards. Study the words in order, shuffle them and show or hide the furigana readings to further test your learning.