The outdoor world is full of secrets. And they are __36__ interesting that quite a lot of people are busy __37__ them.
All around us are birds, animals, trees and flowers. The facts about how they __38__ and grow are as interesting as anything could be.
Do you know that one of __39__ presidents of the USA __40__ hours and hours studying birds? A businessman near New York became so __41__ in insects that he began to get __42__ together. He now has more than one thousand different kinds of insects carefully __43__ in glass boxes.