China's box office makes strong comeback

①China to build 2,500 km high-speed railways in 2023 to advance network ②China's box office makes strong comeback over holiday, generating 6 bln-plus yuan ③China's 3rd polar icebreaker completes trial in Bohai Sea ④Djokovic wins record 10th Australian Open title after downing Tsitsipas ⑤FIFA annual survey reports record transfers globally ⑥Children's immune response to coronavirus fast but doesn't last: Australian research ​⑦Shanghai Museum kicks off new exhibition Botticelli to Van Gogh