Responses to different kinds of questions tend to form clusters.
In other words, relationships tend to form between those who have a high propinquity.
These streets tend to form major 5 or 6-way intersections.
Old parishes tended to form at a time when there were little difference between the church and the state according to the local people.
Like David's, his hair tended to form a natural center part.
Some groups tend to form a historical political and battle image or reputation over time.
For this reason they tended to form distinct communities overseas.
Also, people who have one polyp tend to form others for the rest of their lives.
Online communities tend to form around interests or 'passion points'.
Do you see how they tend to form clusters, with wide stretches of deep water between?