Identifying the Main Idea & Details Directions: Read the passage. Then, fill out the Main Idea chart. Underline the main idea in red. Underline supporting details in blue. Did you know your lungs are the second largest organ in your body? You have two lungs that work together with various other parts of your body. The lungs work together with your heart to draw in oxygen, which is carried by red blood cells across your body. A large muscle called the diaphragm works with your lungs to get air in and out of your body. It rests just below your lungs, near the upper part of your belly. Air then travels down the trachea, the pharynx, and the larynx in that order before passing through two large tubes called bronchi. These large tubes look like trees, expanding and branching out into the spongy part of your left or right lung. Your rib cage is especially important, as it protects this delicate system. As the primary organs of our respiratory system, the lungs’ many functions are quite impressive