1、诚恳说
...To be honest / to tell you the truth / to be frank 说一句实话...Frankly speaking 诚恳说，...To my mind / As far as I’m concerned 在我看来...
2、坦白地说
...franklinite 锌铁尖晶石frankly speaking 坦白地说frankly 坦白地 ...
3、坦白来说
...for the sake of 为了...起见frankly speaking 坦白来说freedom from 免于…的自由 ...
Frankly y speaking老实说;坦白说
And Frankly Speaking而且老实说
Or Frankly Speaking或者坦率地说
Frankly speaking practice gives rise老实说实践出真知
Speaking Frankly坦率地说
Pardon me for speaking frankly恕我直言