you can say that again
US /juː kən seɪ ðæt əˈɡen/
UK /juː kən seɪ ðæt əˈɡen/

1.
used to express complete agreement with something just said
:
•
This weather is terrible!" "You can say that again."
•
That was a long meeting." "You can say that again. I thought it would never end."