Chinanews.com client, July 20 (Xie Yiguan) On July 20, the three major A-share stock indexes fluctuated widely in early trading, and the GEM index shook the red. As of midday closing, the Shanghai index rose 2.62% to 3298.50 points, hitting 3300 points; the Shenzhen Component Index rose 1.74% to 13342.68 points; the GEM index rose 0.47% to 2674.91 points. The half-day turnover of the two cities was nearly 750 billion yuan. On the disk, insurance, building materials, aviation, shipping, securities and other sectors rose the most, while pharmaceuticals and winemaking sectors weakened.