Held at a key juncture ahead of China's two centenary goals, the 19th National Congress of the Communist Party of China will play a vital role in mapping out guidelines for the coming decades and singling out the Party's key tasks, analysts said.

By 2020, China will complete building a moderately prosperous society. By the middle of this century, China should become a modern socialist country that is "prosperous, strong, democratic, culturally advanced and harmonious."

The CPC Central Committee raised the two centenary goals at the Party's 18th National Congress held in November 2012.

As the Party's 19th National Congress is set to open on Wednesday, the world is watching closely on how China moves toward its two centenary goals. The congress comes when China's endeavor to build a moderately prosperous society in all aspects has entered the decisive stage.

In all, 2,287 delegates have been elected from more than 89 million Party members to gather in Beijing to elect a new central committee.

"Whether we can raise comprehensive, strategic and foresighted guidelines [at the congress] concerns the development of the causes of the Party and the nation, the destiny of socialism with Chinese characteristics as well as the fundamental interests of the majority of the Chinese people," Xi Jinping, general secretary of the Communist Party of China Central Committee, said in July while addressing the opening session of a workshop for senior officials.

In the five years since the 18th CPC National Congress, extraordinary developments have occurred in implementing the new concept of development, deepening reforms, enhancing the rule of law, advancing the building of an ecological civilization, pushing forward the modernization of national defense and the military and carrying forward major country diplomacy.

In the economic sphere, Xi has promised extensive supply-side structural reform, including reducing pollution and phasing out excess capacity. The country is seeking progress while maintaining stability and adapting to the new normal of economic development, by pursuing innovative, coordinated, green, open and shared development.

China's rural population living in poverty has decreased from 770 million to 55.75 million between 1978 and 2015. An additional 12.4 million were lifted out of poverty last year, and China is aiming to lift all people out of poverty by 2020.

In the CPC's fight against corruption, crushing momentum has been made in punishing both low-level "flies" and high-ranking "tigers," including heavyweights Zhou Yongkang, Bo Xilai, Guo Boxiong, Xu Caihou, Sun Zhengcai and Ling Jihua.

The past few years also marked China's transition from a player in global affairs to a leader of the global agenda. China hosted the BRICS Summit in September, the Belt and Road Forum for International Cooperation in May, the G20 Hangzhou Summit last year and the APEC Summit in 2014, prescribing remedies for global economic governance.

During the 19th CPC National Congress, the Party is expected to further elaborate on how to rule itself, how to lead the world's largest developing nation to lift more people out of poverty and advance key reforms as well as how to build a community of shared destiny for all humankind, observers said.

Zhu Lijia, a professor of public administration at the Chinese Academy of Governance, said that poverty alleviation, the construction of an ecological environment and development risks are major reform and development tasks in the five years after the 19th CPC National Congress.

Concrete achievements should be made to complete the tasks, which are important to the first centenary goal?- building a moderately prosperous society, Zhu said.

"We are looking forward to the new ideas, policies and measures raised by the 19th National Congress," he said, adding that the congress will have deep influence toward the fulfillment of the second centenary goal.

Li Chengyan, head of Peking University's Center for Anti-Corruption Studies, said that the CPC has established an effective mechanism for self-supervision in the past five years and it is important that such measures be sustained after the 19th National Congress.

The congress will have long-term influence on the country, not only for the next five years, but also for decades to come, as it will make guidelines for the country's second centenary goal, he said.

Yan Jirong, a professor at the Peking University School of Government, said during the 19th National Congress, leaders will appraise the measures taken in the past years to decide which will be enhanced or adjusted.

The 2020 goals set by the CPC?- all benchmarks of China becoming a prosperous country?- are objectives without any "gray areas involved", said Shannon Tiezzi, an editor at The Diplomat magazine.

Zhou Jin contributed to this story.