

この花はきれいですね。
駅の近くにきれいなホテルがあります。
私の部屋はきれいじゃないです。
"きれい(綺麗)" is in the lesson "Adjectives 1" (Level 2), along with 15 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.