You'll never know how much.

4 seconds sound clip from the Remember the Night (1940) classic radio play.

You can hear this line at 00:39:04 in the radio play.

Quote context

[...]

- Just a minute, Jack. I was just...

- Oh, Mrs. Sargent.

- I'm sorry to disturb you, dear, but you'll be in such a rush in the morning...

- Oh, no, you're not disturbing me. Come in.

- Thank you.

- First of all, I want you to know how glad we've been to have you here, and how much I hope you've enjoyed your stay.

- You'll never know how much.

- And then... Well, I want you to know how sorry I am that you're in trouble and how much I hope it'll come out all right.

- I didn't know you knew about that.

- Oh, you poor child. You can be sure I never would have mentioned it now, only...

- Well, has Jack ever told you anything about his childhood?

- No, why?

[...]