1- Yangdi, Wendi's son, wanted to expand China's territory, rebuilt the Great Wall, and built the Grand Canal system which helped unite China's economy. It made farmers mad because they had to work on these projects and pay high taxes. The army took control and killed Yangdi and ended the Sui dynasty.
The canal was built in order to easily ship grain from the rich farmland in southern China to the capital city in Beijing. This also helped the emperors to feed the soldiers guarding the northern borders. The Ancient Chinese built early canals to help with transportation and commerce.
2- Chinese imperial examinations were a civil service examination system in Imperial China for selecting candidates for the state bureaucracy. The exams served to ensure a common knowledge of writing, the classics, and literary style among state officials. This common culture helped to unify the empire and the ideal of achievement by merit gave legitimacy to imperial rule. The examination system played a significant role in tempering the power of hereditary aristocracy, military authority, and the rise of a gentry class of scholar-bureaucrats.
3- Buddhism played a dominant role in Tang dynasty China, its influence evident in poetry and art of the period. Buddhist teachings spoke to the concerns of salvation and the release from suffering and flourished during the period of political disunity in China (220-581) after the fall of the Han dynasty.
4- The Mandate of Heaven is a Chinese political and religious teaching that was used in ancient and imperial China to justify the rule of the King or Emperor of China. According to this belief, Heaven embodies the natural order and the will of the just ruler of China, the "Son of Heaven" of the "Celestial Empire".
