The People's Republic of China_____on Oct.1,1949.A.found B.was found C.is found D.was founded选了B,但是答案是D,为什么?find的过去分词有加ed吗?

the people's choice the People’s Republic of the People's Liberation Army. the location of the people's square Children go to people's houses and scare the people. the people's republic of china缩写 the people’s republic of china中文翻译 The people 's republic of china the people’s Republic of china The panda are people's friends是什么意思 The world's people are hypocritical.. 人民公园前加the peoples park People's Government前面加不加The ? Doctr can s（ ） the ill people. Act of the People’s Republic of the people 's life of beijing 还是the people of beijing 's life Some people are (s ) at the supermarketSome people are (s ) at the supermarket首字母填空 Shanghai Museum is in ______ wine.a.the people square b.the people'square c.people's squared.people square