Despite many difficulties, she persevered in learning English.

persevered 是动词 persevere 的过去式形式。persevere 由前缀 per-（表示"彻底、完全"）和词根 severe（"严格、严厉"）组成，意思是"坚持不懈、不屈不挠"，指在面对困难时仍然持续努力。