Answer:
The words, form and shape, are closely related to the words, structure and pattern.
Explanation: Writers of the classical period constructed their works according to a pattern they had learned. They had to be creative within the forms and norms of the period.
Dictionary: Formal (2nd definition) following or according to establised form, custom, or rule. (Merriam-Webster)
Formal: using an agreed and often official or traditional way of doing things. (Cambridge)
