病(びょう)気(き)の() byoukinoため tame彼(かれ) kareは wa仕(し)事(ごと) shigotoが ga出(で)来(き)な()か()っ()た() dekinakatta。 He couldn't work because of his illness. Literal Illness [because-のため] he [topic-は] work [subject-が] couldn't-do. 仕事が出来なかった uses the formal potential 出来る (できる). のため marks illness as the cause. A straightforward cause-and-effect sentence. workhealth~ことができる (can do)~のため (because of)
病(びょう)気(き)の() byoukinoため tame彼(かれ) kareは wa仕(し)事(ごと) shigotoが ga出(で)来(き)な()か()っ()た() dekinakatta。 He couldn't work because of his illness. Literal Illness [because-のため] he [topic-は] work [subject-が] couldn't-do. 仕事が出来なかった uses the formal potential 出来る (できる). のため marks illness as the cause. A straightforward cause-and-effect sentence. workhealth~ことができる (can do)~のため (because of)