Complex sentence: Justine Henin put together a strong season, winning 10 out of the 14 events she entered during the season, including her sixth and seventh Grand Slam titles at the French Open and U.S. Open, and put together a 63--4 win-loss record.
Split into simpler sentences: Justine Henin put together an exceptional season, winning 10 out of the 14 events she entered. This included her sixth and seventh Grand Slam titles at the French Open and U.S. Open, whilst compiling a 63--4 win-loss record.