Nà duàn rìzi fēicháng jiānnán, tā chéngshòu le jùdà de yālì.
Those days were very hard; he bore enormous pressure.
Tips
usage
艰难 emphasizes the difficulty of a process or decision. It's more literary/formal than 困难 (kùnnan, difficult). Compare: 艰苦 = harsh conditions, 艰难 = difficult situation/process, 困难 = general difficulty.
