

将来、便利なロボットを発明するのが夢です。
電話を発明したのは誰ですか。
そんな機械はまだ誰も発明していませんよ。
"はつめいする(発明する)" is in the lesson "Verbs 5" (Level 17), along with 11 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.