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Student or Learner
Is there subtle difference in the meaning between "1" and "2"?
1. He was so drunk he fell down.
2. He was so drunk he fell over.
I think that fell over might sound a bit worse, like collapsing face down rather than losing balance.
There is a commonly-used phrase - "falling-down drunk" to describe a person who has had too much alcohol and who can barely stand up as a result.
How was John last night?
Oh, he was falling-down drunk! It was very funny.
I don't think I've ever heard "falling-over drunk" used.
Having said that, I see little difference, if any, between being so drunk that you fall down and being so drunk that you fall over.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.