Structural:
Structures in a design usually address the question "what" and are represented using nouns and adjectives
Structures in a design are physical elements, conceptual objects, attributes, fields, or arrangements of other structures.
Behavioral:
In a template, behaviors usually address the questions of "how" and "when," and are typically represented using verbs and adverbs.
Behaviors are actions, forces, processes, or controls imposed on or by a system in relation to its external environment.