“发奋”常见的英文表达有 “strive vigorously”、“make great efforts” 或 “work hard with determination” 等，具体使用可根据语境选择：
Strive vigorously：强调以饱满的热情和活力去努力，有积极向上、全力以赴的意味。
例句：He decided to strive vigorously for his dream of becoming a successful entrepreneur.（他决定为成为成功企业家的梦想发奋努力。）
Make great efforts：突出付出大量精力、投入很多去做某事，侧重于努力的程度。
例句：She made great efforts to improve her English skills for the upcoming international conference.（为了即将到来的国际会议，她发奋努力提高英语技能。）
Work hard with determination：既包含努力工作，又强调有坚定的决心，突出意志层面的坚定。
例句：The team worked hard with determination to win the championship.（这个团队发奋努力，决心赢得冠军。 ）