求热带雨林的英文解释！！！急！！！

Rainforests are forests characterized by high rainfall, with definitions setting minimum normal annual rainfall between 1750–2000 mm (68-78 inches). The monsoon trough, alternately known as the intertropical convergence zone, plays a significant role in creating Earth's tropical rain forests.

From 40 to 75% of all species on Earth are indigenous to the rainforests.[1] It has been estimated that many millions of species of plants, insects, and microorganisms are still undiscovered. Tropical rainforests have been called the "jewels of the Earth", and the "world's largest pharmacy", because of the large number of natural medicines discovered there.[2] Rainforests are also responsible for 28% of the worlds oxygen turn over, often misunderstood as oxygen production,[3] processing it through photosynthesis from carbon dioxide and through breathing to carbon dioxide.

The undergrowth in a rainforest is restricted in many areas by the lack of