An HC completes the phrase in dominant, making the phrase feel not only incomplete and unresolved, but leaving it in the dominant area specifically adds tension to the point where your ear can only be satisfied by hearing another phrase that provides the answer. Half Cadences always finish on a V but can come from any chord before it. Most often, it will come from a Tonic area or Predominant area before moving to Dominant on this final V chord.
An outline is being defined as a 2 dimensional shape which is the answer. The outline also known as the list being arrange to portray the hierarchical relationship and known as a tree structure. It is used in order to portray the main points or a topic in a subject.
