One in five<span> teenagers in America can’t hear rustles or whispers, according to a study published in August in The Journal of the American Medical Association. These teenagers exhibit what’s known as slight </span>hearing loss.<span> The number of teenagers with hearing loss from slight to severe has jumped 33 percent since 1994.</span>
The author is using both of these comparisons to express the idea that, when learning to do something new it's difficult at first until you understand the activity or topic better.
