SHANGHAI - Since the 2008 Beijing Olympic Games, Chinese swimmers have claimed obvious improvement and aim to make breakthroughs at the 2012 London Olympic Games.

China won one gold, three silver and two bronze medals three years ago at the Beijing Games, and they moved up to take four golds and two silvers at the 2009 Rome world championships.

The Chinese team are taking part in the 14th FINA World Championships in Shanghai, and according to head coach Yao Zhengjie, they take the Shanghai worlds as an important experience for the 2012 Games.

"The Shanghai worlds is very important as it is the last worlds before the Olympic Games," Yao said on Tuesday. "We will take it as a good chance to find out problems and prepare for the London Games. Hopefully we can make some breakthroughs in London."

Team leader Xu Qi said the qualification of the London Games will be decided by the swimmers' results from the worlds till next year before the Games.

"We will look at the results to decide who will appear in London," Xu said. "There is Olympic qualifying time and Olympic selection time, and if a swimmer reaches the time, he can qualify for the Games."

According to the official website of FINA, there will be 34 swimming events in the London Games and 900 athletes will take part in. An athlete should reach the Olympic qualifying time or at least reach the FINA/Olympic Selection time approved by FINA to get a berth.

Swimming wunderkind Sun Yang will be China's gold hopeful for the London Games, and the 19-year-old is expecting his first world championships title here in Shanghai.

Sun took a silver in the men's 400m freestyle Sunday and he will also compete in the 800m and 1500m free.

"I hope I can get better results in my other events," said Sun, who was only 0.87 second off Australian Grant Hackett's 2001 world record in the men's 1,500m  freestyle at the Asian Games in last November. "And my goal is to win a gold in London."

Zhao Jing will be the favorite in women's 100m and 200m backstroke in London as the 20-year-old, winner of the 50m backstorke at the Rome worlds, claimed the 100m back gold Tuesday.

"The gold medal has a significant meaning to me. It is definitely a huge boost to my confidence in my build-up to the London Olympic Games," said Zhao, who burst into tears after the winning the title.

Besides, 15-year-old Ye Shiwen, winner of the women's 200m individual medley at Shanghai, and 17-year-old Li Xuanxu, bronze medalist of the women's 1,500m free, will also be China's gold hope at the 2012 Games.

Apart from those young swimmers, there are also some strong veterans in the Chinese team.

Beijing Olympic champion Liu Zige, though she failed to take a medal in the women's 100m butterfly at Shanghai, will try her best to retain her title in the 200m butterfly in London, and Olympic runner-up Jiao Liuyang is the other favorite in the event.

World champion Zhang Lin has experienced a difficult time since the Asian Games last year and he will only take part in the relay event at Shanghai. However, there's still one year away to the London Games and Zhang will possibly still be a leader at the 2012 Games.