When was Buddhism first introduced into China?
佛教是什么时候传入中国的？

It is difficult to ascertain the exact time of the introduction of Buddhism into China. In the early years of its introduction, its followers were few and may not have been noticed by the upper bureaucracy and historians. In the year 2 BC, Yi Cun, the envoy of the king of Great Kuṣāṇa (a kingdom established by a powerful minority ethnic group after its migration from Gansu, China, to Central Asia), arrived in Chang'an (present-day Xi'an), capital of the Han Dynasty. He recited Buddhist teachings to a high-ranking scholar-administrator named Jing Lu. This is the earliest record of the introduction of Buddhism into China. We may presume that 120 years before this, with the opening up of communication with the Western Regions by Emperor Wu of the Han Dynasty, Buddhism, which had spread from India to Central Asia, was probably already being carried eastward by travelers. According to another tradition, at the time of Qin Shihuang (who reigned during 246-210 BC, contemporaneously with AŚoka in India, who reigned during 272-226 BC), 18 Indian samaṇas—Sri Fang and others—came to Xianyang (near present-day Xi'an). After the Third Buddhist Council, held in about 250 BC during the reign of AŚoka, Buddhist missions were sent to various countries, so it is quite possible that a mission came to China. Besides, some identify the word "Xianmen" which appears in Song Yu's Ode of Gao Tang and the Biography of Qin Shi Huang in the Annals of History with the word "Samaṇa". Yet this is hard to verify since there are no extant translations or other books on the matter.
佛教传入中国的具体时间和年代，现在很难考定。最初传入时，不过在少数人中奉行，未必为上层官府和史官之流所注意。公元前2年，大月氏国（原居我国甘肃的一个强盛的少数民族西迁中亚后建立的国家）国王的使者伊存到了当时中国的首都长安（即今西安），他口授佛经给一个名叫景卢的博士弟子，这是中国史书上关于佛教传入中国的最早的记录。我们可推断，由于在此一百二十年前汉武帝开辟西域交通的结果，当时由印度传布到中亚细亚的佛教很可能早已通过行旅往来而向东方渐进。也有传说：在与印度阿育王（约公元前272—公元前226在位）同时的秦始皇（公元前246—公元前210在位）时代，已有印度的沙门室利房等十八人来到我国咸阳。阿育王时举行第三次结集约在公元前250年，会后派大德赴各国传教，前来中国很有可能。另外，也有认为宋玉《高唐赋》和《史记·始皇本纪》中的“羡门”即沙门的，但因无译述学说传世，无从确考。