“勤勉地”的英语可以翻译为：assiduously，diligently ...

他们说他们除了勤勉地在报纸中厌恶广告削减出自折扣券.They say they hate ads in newspapers but diligently cut out coupons.他勤勉地履行职责.He was assiduous in performance of duty.勤勉地看, 而且注意你的数字.Diligently look at, and attend to your figure....