meths

例句：

1. 1. 名词：methane，甲烷。2. 动词：methane is a colorless, odorless gas that is used in refrigeration and air conditioning systems.
   甲烷是一种无色无味的气体，用于制冷和空调系统。
2. 4. 例句：1. Methane is a colorless, odorless gas that is used in refrigeration and air conditioning systems.
   甲烷是一种无色无味的气体，用于制冷和空调系统。
3. 2. The production of methane is a major source of greenhouse gas emissions.
   甲烷的生产是温室气体排放的主要来源。
4. 3. Methane is a colorless, odorless gas that is used in refrigeration and air conditioning systems.
   甲烷是一种无色无味的气体，用于制冷和空调系统。