Hi,
I read that that above sentence suppose to mean "extreme fatigue".
Can someone explain the function of が in the phrase? Is 激（はげ）しい functioning as a verb?
This is your typical が -- that is, it means fatigue is the subject.
激（はげ）しい is an adjective describing the fatigue. As a complete sentence it would be more correct to translate it as "The fatigue is extreme."
This is your typical が -- that is, it means fatigue is the subject.
激（はげ）しい is an adjective describing the fatigue. As a complete sentence it would be more correct to translate it as "The fatigue is extreme."