text_1: In 2020, two school boys in China died suddenly after wearing face masks during physical exercise.
text_2: What's true: In April and May 2020, multiple Chinese news outlets reported that two boys, aged 15 and 14, had died in late April after collapsing during gym class at schools in Henan and Hunah provinces. What's undetermined: It's unknown whether the boys' wearing face masks played any role in their deaths, or was coincidental.