this topic is quite interesting.
According to Kennedy, a corpus is a body of written text or transcribed speech which can serve as a basis for linguistic analysis and description.
here is a keyword: body or corspe
What shall we concentrate on?
Then we come back to a classic question: parole or langue; performance or competence.
The difference between dead and alive, I think, is equal to the contrast in reading Shakespeare and waching Shakespeare.
Now please study the following conversation:
A: I still have a son.
B: Well, that's OK!
A: I still have a dog.
B: Oh, I'm sorry!
(from Yule)
Even though the words are easy, out of the real situation, we need to guess or work out the meaning of the speakers.
However, if you watch or hear the conversation in person, or you know more information about the speakers, it's easy to understand.
Conversation through QQ is more problematic than common dialogues. And I think you know the reason.