He was weak from a long illness.

由于长期生病他身体很虚弱。

youdao

He was weak from a long illness.

他长期患病后很虚弱。

youdao

She was weak from a long illness.

她因长期生病而十分虚弱。

youdao

Last year, many economists hoped that Zvi Griliches, a noted econometrician who was unquestionably deserving of the prize, and was suffering from a long illness, would win.

ECONOMIST: Nobel prize in economics

And he said that in addition to free prescriptions for people with cancer, charges would also be waived for anyone suffering from a long-term illness.

BBC: NEWS | UK | UK Politics | No time for a novice, says Brown

Scenario two: Marcus Trescothick is sent home from the Ashes tour with a chronic long-term stress-related illness.

BBC: Bitter-sweet sympathy