Original sentence: In the marathon two Korean athletes -- Sohn Kee-chung and Nam Sung-yong -- won medals, running for Japan and under Japanese names.Japan had annexed Korea in 1910
Edited sentence: In the marathon two Korean athletes -- Sohn Kee-chung and Nam Sung-yong -- won medals, forced to run for Japan and under Japanese names.Japan had invaded Korea in  1910, controlling almost all of Korea at the time