Idioms with SAY

let’s say
used when making a suggestion or giving an example
Try and finish the presentation by, let’s say, Wednesday.

let’s just say
used when you do not want to give a lot of details about something
Let’s just say he wasn’t very happy about it.

say no more
used to say that you understand what someone means
“They went to Bali together.” “Say no more!”

say the word
used to tell someone that you will do what they want
Just say the word, and we’ll come and help.

I must say
used to emphasize what you are saying
I must say that I’m not very impressed.