He could be removed from the athletic team.
Also:
Acne
Breast development in men.
<span>myocardial infarction (Heart attack)</span>
Liver cancer
A concussion, as found on Google, is a "temporary unconsciousness caused by a blow to the head.", which means a really hard hit to the head, and then a knock out or a blackout
Some symptoms that are usually associated with a concussion can be but are not limited to: headaches, memory loss (if severe), nausea, vomiting, slurred speech, confusion, and fatigue. There can also be sleep disturbances, sensitivity to any type of change, such as air or light, and disorders of the 5 senses (sound, sight, touch, smell, and taste).
The 3rd one, the one that begins with knowledge
