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彼は病気で苦しんでいる
He is suffering from his illness
to suffer physically or emotionally; to endure pain or hardship
彼女は失恋の苦しみを抱えていた
She was carrying the pain of her heartbreak
彼は貧困の中で苦しんで育った
He grew up suffering in poverty
This verb is often used to describe enduring physical pain, emotional distress, or hardship in life. It can be used in both formal and informal contexts.
'苦しむ' is often used with the particle 'で' to indicate the cause of suffering, as in '病気で苦しむ' (to suffer from illness).
In formal writing or serious contexts, '苦しむ' is appropriate. In casual conversation, you might use softer expressions like 'つらい' (painful) or '大変だ' (it's tough).
Derived from the kanji '苦' (ku) meaning 'suffering' and 'しむ' (shimu) which is a verb suffix indicating a state or condition.
While '苦しむ' can be used in both formal and informal contexts, it is often used in more serious or emotional situations. It is not typically used in casual conversation unless referring to significant hardship.