溶岩

1. Origins, structure, and basic meaning

• Structure: 溶岩 is a noun read ようがん, meaning lava as hot rock material at the surface or after it has cooled and hardened.
• Basic usage: Use 冷えて固まった溶岩 for hardened lava and 溶岩が斜面を流れる for lava flowing down a slope.
  • 資料館で冷えて固まった溶岩に触れました。 describes touching cooled, hardened lava at a museum; 模型を使って溶岩が斜面を流れる様子を説明しました。 describes using a model to explain how lava flows down a slope.

2. Common pitfalls and similar expressions

• 溶岩に触れる
  • に marks the hardened lava that was touched at the museum.
• 溶岩が流れる
  • が marks lava as the material flowing down the slope.
• 模型を使って説明する
  • を使って identifies a model as the means used to explain the flow instead of presenting actual lava.