The Norton Anthologies of literature always do a good job with summarizing the different periods on their website and in their textbooks. A link is included below. When writing a conclusion about the age of Chaucer, one could discuss any similarities and differences from then and today's world. For example, Chaucer's world revolved around the Catholic church, but not everyone was pious. Is that similar or different from today? Also, one could focus on the language and how it has evolved since his time and how it is used today. The Medieval world was dark and very primitive, remember. Technology was at its best with the candle and the wheel at that time; but even so, Chaucer was able to capture the human condition in a variety of ways and through a variety of characters. His storytelling abilities must have mirrored the best types of tales that were told in front of the fireside at night in the homes of peasants and nobles alike.