、。
Every time she coughed, she suffered terribly.
Literal
She [topic-は] cough [object-を] do [every-time-たびに], very suffered.
~たびに ('every time / whenever') attaches to a verb in plain form (or a noun + の) and expresses 'each time X happens, Y happens' — the pattern emphasizes recurrence with parallel results. 咳をする ('to cough,' literally 'do a cough') is the canonical noun-plus-suru phrase: Japanese tends to package symptoms and bodily acts with する (くしゃみをする 'sneeze,' あくびをする 'yawn'). 苦しむ ('to suffer, be in pain / distress') is broader than 痛む ('hurt physically') — covering physical, emotional, and existential suffering. The とても ('very') intensifies, and the past tense locks the description into a completed past stretch — perhaps a recovery story being recounted.