This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
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Question: Passage: On 30 September, Zhou Enlai warned the United States that China was prepared to intervene in Korea if the United States crossed the 38th parallel. Zhou attempted to advise North Korean commanders on how to conduct a general withdrawal by using the same tactics which had allowed Chinese communist forces to successfully escape Chiang Kai-shek's Encirclement Campaigns in the 1930s, but by some accounts North Korean commanders did not utilize these tactics effectively. Historian Bruce Cumings argues, however, the KPA's rapid withdrawal was strategic, with troops melting into the mountains from where they could launch guerrilla raids on the UN forces spread out on the coasts. Question: Who vowed to intervene if the US was to engage in conflict North of the 38th parallel?

Answer: China


Question: Passage: In 179 BC Philip died. His talented and ambitious son, Perseus, took the throne and showed a renewed interest in conquering Greece. With her Greek allies facing a major new threat, Rome declared war on Macedonia again, starting the Third Macedonian War. Perseus initially had some success against the Romans. However, Rome responded by sending a stronger army. This second consular army decisively defeated the Macedonians at the Battle of Pydna in 168 BC and the Macedonians duly capitulated, ending the war. Question: Who had initially begun the Third Macedonian War?

Answer: Rome


Question: Passage: Eritrea is a multilingual country. The nation has no official language, as the Constitution establishes the "equality of all Eritrean languages". However, Tigrinya serves as the de facto language of national identity. With 2,540,000 total speakers of a population of 5,254,000 in 2006, Tigrinya is the most widely spoken language, particularly in the southern and central parts of Eritrea. Modern Standard Arabic and English serve as de facto working languages, with the latter used in university education and many technical fields. Italian, the former colonial language, is widely used in commerce and is taught as a second language in schools, with a few elderly monolinguals. Question: What is the official language of Eritrea?

Answer:
The nation has no official language