to tell the truth
US /tə tel ðə truːθ/
UK /tə tel ðə truːθ/

1.
说实话, 老实说
used to introduce a statement of fact or opinion, often one that is surprising or unexpected
:
•
To tell the truth, I don't really like his new song.
说实话,我不太喜欢他的新歌。
•
He said he was busy, but to tell the truth, he was just avoiding me.
他说他很忙,但说实话,他只是在躲着我。