In all honesty/frankness/sincerity,ie speaking with the greatest honesty,etc
最诚实地/坦白地/真诚地
I gave him my sincere thanks.
我真诚地向他道谢。
behave cold and formally.
非常冷淡、不真诚地行事。
Believe me, I am truly grateful for...
我确实真诚地感谢你……
Sincerest congratulations on your birthday.
真诚地祝你生日快乐。
He sincerely converted to Judaism
他真诚地改信了犹太教。
I sincerely hope that this first transaction
我真诚地希望这次交易
Your very sincere well-wisher A. Lincoln
真诚地祝福你的A.林肯。
He loved his wife devotedly.
他真诚地爱他的妻子。
I promised you faithfully.
我真诚地向你承诺。
I earnestly hope that you will succeed.
我真诚地希望你成功。
We cordially wish it a success.
我们真诚地希望它成功。
The government has acted in good faith.
政府一直在真诚地施政。
But indeed I would love you fondly and truly.
但是真的，我会亲切地，真诚地爱你。
I had a sincere desire to help her, so I told her with simplicity and sincerity.
我真诚地想帮助她，所以坦率、诚恳地告诉了她。
They liked each other honestly-they were both honest.
他们俩真诚地彼此受慕着--他们都是诚实的人。
I sincerely hope you will soon recover.
我真诚地盼望你不久就会恢复健康。
I sincerely hope we transaction can be concluded.
我真诚地希望能做成一笔买卖。