To Cure
To Heal, To Ease
transitive verb, godan verb
The kanji means cure, so this verb means to cure, to heal or to ease something.
This verb is for when someone actively cures something. (The illness doesn't just get better on its own.) How can you remember that? Because when you try to cure someone and you mess up, they can sue (す). Basically, to cure someone is to risk getting sued.
This word uses a kun'yomi reading you didn't learn with the kanji, so here's a mnemonic:
I need you to cure him, and I need you to cure him right now (なお). NOW NOW NOW!
This also shares a reading with 直す, a similar word that you already learned means "to fix." Fixing and curing are basically the same, right? Call me crazy, but there might just be an etymological connection there that can help you remember this reading.
この病気を治すには薬が必要です。
Medications are needed to cure this disease.
キズを早く治す方法を知っていますか？
Do you know how to heal scratches fast?
ノドのイガイガを治すには、ネギを首にくくっておくのが一番です。
To cure a scratchy throat, it's best to tie a leek around your neck.