Hobbies are important for many reasons. First, a hobby can be educational. For example, if the hobby is stamp collecting, the person can learn about the countries of the world and even some of their history. Second, engaging in a hobby can lead to meeting other people with the same interests. A person can also meet other people by going to the school. Third, a person's free time is being used in a positive way. The person has no time to be bored or get into mischief while engaged in the hobby. Finally, some hobbies can lead to a future job. A person who enjoys a hobby-related job is more satisfied with life.
这段话的topic sentence很明显-“Hobbies are important for many reasons”,
之后的支持句从三方面阐述hobby的重要性(first, second, third),并用Finally进行段落总结。
但段中这句话"A person can also meet other people by going the school"与hobby重要的原因没有关系,因此削弱了整个段落的连贯性与统一性,应该被去掉。