To Stop
intransitive verb, godan verb
This word consists of kanji with hiragana attached. Because the hiragana ends with an う sound, you know this word is a verb.
This is an intransitive verb. That means it does not take a direct object. Something comes to a stop. No direct object here. That's why this verb means to stop.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You learned this reading when you learned the 止める, so you should be able to read it already!
この白いラインで車が止まる。
Cars stop at this white line.
スケートリンクの上で、止まることができなかった。
I couldn't stop on the skating rink.
バスは、もう少しで止まりそうでした。
The bus almost stopped.