The author's prior knowledge with some opinions from others
The topic which best completes the idea web is the following one:
Value of volunteering.
When volunteering, one gets to meet new people and could make friends with them. It is also an accomplishment, since volunteering is a way to actually do something concrete. It also leads to satisfaction because being able to help is a source of joy. Besides, volunteering is a way to improve one's community, since the whole idea of it is making something better by offering help. Therefore, the idea web shows what volunteering can bring and do. In other words, it shows its value.
