

泳ぐのが下手で、すぐ沈むんです。
力を抜けば、体は水に沈まないですよ。
ボートに穴があいて、ゆっくり沈んでいきました。
"しずむ(沈む)" is in the lesson "Sports 1" (Level 23), along with 13 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.