

教科書の二十ページを開いてください。
家に教科書を忘れました。
新しい教科書はもう買いましたか。
"きょうかしょ(教科書)" is in the lesson "Education" (Level 35), along with 10 other useful words. LinDuo has 180 topic lessons like this one, 2,379 words in total. Every word has an illustration, a transcription and pronunciation in a female and a male voice. Just 10–15 minutes a day is enough to learn them all. Free, and works offline.