Read the following excerpt from a student essay. How can the writer best improve his or her sentence fluency?
If you want to improve your life, consider exercise. Exercise does more than just help to build stamina and strength. It can help you control your weight. It can also reduce your chances of getting a serious illness, helping ward off a variety of conditions, such as arthritis, heart disease, high blood pressure, high cholesterol, loss of muscle mass, osteoporosis (bone loss), stroke, and type 2 diabetes. It can improve your mood by releasing endorphins and lowering stress levels, decreasing the likelihood of depression and anxiety. Exercise can even help you sleep better. For these reasons, people should aim to exercise every day.

 - by varying sentence length
 - by varying the beginnings of sentences
 - by using more complex sentence structures
The writer could best improve his or her sentence fluency by varying the beginnings of sentences.
For example, the writer could revise the underlined text.
If you want to improve your life, consider exercise. Exercise does more than just help to build stamina and strength. It can help you control your weight. It can also reduce your chances of getting a serious illness, helping ward off a variety of conditions, such as arthritis, heart disease, high blood pressure, high cholesterol, loss of muscle mass, osteoporosis (bone loss), stroke, and type 2 diabetes. It can improve your mood by releasing endorphins and lowering stress levels, decreasing the likelihood of depression and anxiety. Exercise can even help you sleep better. For these reasons, people should aim to exercise every day.