"I've been seventy four" - what does it mean? Is it something about drugs?
Any context? Where did you hear it?
For the moment I thought he said: "I have smoked before" but it didn't sound so distinctly.

It's from the Mean Creek movie:
Marty: "Wanna smoke a birthday doobie?"
Rocky: "Sam doesn't smoke weed, Marty!"
George: "I've been seventy-four."
Marty: "Yeah?"
George: "Yeah, I... I've smoked the whole blunt myself. I hallucinated. There was a little blue guy on my shoulder tap-dancing."
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Hm... I think I didn't catch what he said.
He asked Milly then: "Have you been soaked before?". At least I think it was soaked what I heard.
So, am I right? Does it sound natural?
Was it

'stoned before'?
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No, there were not any ts.

slang. to soak - to drink alcohol - to bib
http://dict.die.net/soaked /
Here is that part. You can hear it. Please tell me what you hear.
http://www.nvtc.ee/~mwb/soaked_low.mp3 (352 kb)
That link doesn't work for me but Grammar Geek listened to it in your other post and has confirmed that it is 'stoned'.
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