Emphysema is a form of chronic (long-term) lung disease. People with emphysema have difficulty breathing from a limitation in blowing air out. There are multiple causes of emphysema, but smoking is by far the most common.Emphysema is one of the main types of chronic obstructive pulmonary disease (COPD).ost commonly, the toxins in cigarette smoke create the damage. The lung changes of emphysema evolve slowly over years: 1  As the fragile tissues between air sacs are destroyed, air pockets in the lungs develop. 2  Air becomes trapped in these spaces of damaged lung tissue.
Tone is an author's style or manner of expression. It gives the   reader clues as to how the author feels about his/her subject.
To answer this question, we need to start with the definitions of what tone and themes actually are. So: Tone is the general feeling of the text. It has more to do with the way in which the author intends for the reader to feel while reading the work. For instance, a story about a child playing with a puppy can have a light, happy tone, whereas a poem about the death of a loved one will have a dark or sad tone.