genuinely是真诚地的意思，而sincerely则是真挚地的意思，区别可以从以下例子看出：

I am writing to my friend, thank him genuinely for his warm hospitality, and treat me as his sincerely friend. 我写信给我的朋友，真诚地感谢他的热情款待，并把我当作他真挚的朋友。