Changes with Age. In most cases, a person's normal respiratory rate will change with age; younger adults, children, and babies will typically have faster respiratory rates, because as people age, their breathing usually slows down.
Modic changes are pathological changes in the bones of the spine, the vertebrae. These changes are situated in both the body of the vertebrae and in the end plate of the neighboring disc.
3rd (they). have do. had did. There is a type of auxiliary verb called a modal which changes the meaning of a verb in different ways. Words like can, should, would, may, might, and must are modals and are covered in other lessons. There are other lessons that cover the use of verbs.