1. Why is the Amazon called the "lungs of the Earth"?

В тексте сказано: "The Amazon rainforest in South America is the largest tropical rainforest in the world. It is often called the "lungs of the Earth" because its millions of trees produce about 20% of the world's oxygen."

Амазонку называют "легкими Земли", потому что миллионы деревьев в этом лесу производят около 20% кислорода в мире.

Ответ: The Amazon is called the "lungs of the Earth" because its millions of trees produce about 20% of the world's oxygen.