Many athletes work hard to rehabilitate in hospitals after getting some injuries. Many athletes work hard only to be rehabilitated in hospitals after having some serious injuries.

When I had a sore throat, it was really hard to ingest anything even the water. 

When I use my earphone, entangled earphone wire makes me irritated.

Working overtime just to show for senior we work hard is an endemic problem in Korean company's culture. =Working overtime just to show your seniors that you're working hard is an endemic problem in Korean culture.

Because of the huse deficit, building ship companies reduce the number of their employees drastically. Because of the a huge deficit, ship building companies drastically reduce/limit the number of their employees.