You do it this way; the shift in perspective can bewilder the reader. Consistency is the chief virtue here. There is, of course, a difference between a process essay that tells readers how to do something and a process essay that describes the process by which something gets done by someone else or by nature.here is, of course, a difference between a process essay that tells readers how to do something and a process essay that describes the process by which something gets done by someone else or by nature.
In the human heart, the pulmonary trunk (pulmonary artery or main pulmonary artery) begins at the base of the right ventricle. It is short and wideâapproximately 5 centimetres (2.0 in) in length and 3 centimetres (1.2 in) in diameter.
The pulmonary arteries send blood to the lungs to become oxygenated. It is then circulated throughout the body in a process known as respiration. The pulmonary arteries send blood to the lungs to become oxygenated.