Of all the Tang and Song achievements, which one was the most important? Why do you think so? Explain your answer in 75 to 100 words. Be sure to support your answer with evidence.

The Tang era is considered the greatest age for Chinese poetry. Such was the importance of poetry that skills in composing poems were required to pass the imperial examinations. Many prominent Chinese poets belonged to the Tang age including Li Bai, often considered the greatest Chinese poet of all time; and Du Fu, another all-time great who is called the "Poet-Historian". Poetry styles that were popular in the Tang were gushi, unregulated or "old (or ancient) poetry"; and jintishi, regulated or "modern-form poetry".