改句子：Great changes have taken place in Hangzhou since 1999

Great changes have taken place in my hometown since 1930. "Great changes have taken place in China since the introduct Great changes have taken place since liberation 英语按要求该句子Great changes have taken place in China since libera Great changes have taken place ...in china Great changes have taken place in China. 把Since than great changes have taken place there.改成正确的句子 Great changes have taken place since then in the factory ___ Great changes have taken place since then in the factory (wh A great many changes have taken place in China since…的意思? Great changes ___ place in Hebei since 1980.A.have taken B.h 7.great changes have taken place since then in the factory _