"a Chinese"; 136,000 results

An interesting read (AUE):
"A single Chinese..." - Poll

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https://www.englishforums.com/English/HeIsJapaneseAJapanese/xmhwv/post.htm
"he is a Japanese" vs  "he is Japanese"

http://forum.wordreference.com/threads/im-chinese-im-a-chinese-nationality-adjective-vs-noun.1712120/
"I am Chinese" vs "I am a Chinese"

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