Oh, no. You don't know what you're saying. It's no good. It couldn't work.
5 seconds sound clip from the Shockproof (1949) movie soundboard.
You can hear this line at 00:40:01.723 in the Blu-ray version of the movie.
Quote context
[...]
- I know I'm no great prize. I don't make much money, although I have hopes.
- I'm just an everyday guy. I don't care much about night clubs. I'm not a very good dancer.
- I guess I like mostly what you might call simple things.
- I can't offer you the expensive gowns, the expensive times that Harry Wesson can.
- But I do love you, Jenny. Will you marry me, Jenny?
- Oh, no. You don't know what you're saying. It's no good. It couldn't work.
- No, it's not that. It's just you don't know me.
- You know something? You're the first man who ever asked me to marry him.
[...]