Complex sentence: The Chinese Olympic Committee confirmed that Hangzhou has submitted the bidding, and is the only city to declare the candidacy, if successful, they will become the third city in China to host the Games after Beijing in 1990 and Guangzhou in 2010.
Split into simpler sentences: The Chinese Olympic Committee confirmed that Hangzhou submitted a bid, and is the only city to declare the candidacy. If successful, they will become the third city in China to host the Games after Beijing in 1990 and Guangzhou in 2010.