... vipers are nocturnal and lightning quick.

[Tait-ka]

Typically located in India, China, and Asia; these vipers are nocturnal and lightning quick. Moreover, if you do get bit by one, you’ll feel it immediately.
Furthermore the bite will swell and you’ll begin to bleed from your mouth, as your blood pressure plummets, and your heart rate slows.

Source:

All That Slithers: The Deadliest Snakes On Earth | Journalistate

Slimy, slithery, and seriously dangerous. Granted we could be talking about a number of things here, but in this case, we’re discussing one of the world’s...

journalistate.com

1) The semicolon looks wrong to me. I think there should be a comma instead of a semicolon. Right?
2) What does "lightning quick" mean?
3) "the bite will swell" sounds illogical - the skin (on which the snake bites) swells, not the bite. Right?
4) Can I also say "your mouth will begin to bleed" or "the bleeding will start from your mouth" instead of "you’ll begin to bleed from your mouth"?

 

[emsr2d2]

Typically located in India, China, and Asia; these vipers are nocturnal and lightning quick. Moreover, if you do get bit by one, you’ll feel it immediately.
Furthermore the bite will swell and you’ll begin to bleed from your mouth, as your blood pressure plummets, and your heart rate slows.

Source:

All That Slithers: The Deadliest Snakes On Earth | Journalistate

Slimy, slithery, and seriously dangerous. Granted we could be talking about a number of things here, but in this case, we’re discussing one of the world’s...

journalistate.com

1) The semicolon looks wrong to me. I think there should be a comma instead of a semicolon. Right?

You're right. It should be a comma.

2) What does "lightning quick" mean?

Don't you think lightning is pretty fast?

3) "the bite will swell" sounds illogical - the skin (on which the snake bites) swells, not the bite. Right?

Technically, yes.

4) Can I also say "your mouth will begin to bleed" or "the bleeding will start from your mouth" instead of "you’ll begin to bleed from your mouth"?

No to the first, yes to the second.

 

[Tait-ka]

yes to the second.

To me, the problem with the wording "The bleeding will start..." is that it presupposes that we already know about bleeding, our only question is where it will start from. The original is giving us completely new information: "You'll begin to bleed." Then it tells us the source of the bleeding: "from your mouth."

So I guess "The bleeding will start..." is not appropriate to use in the context of post #1.

Do you not think it this way?

 

[emsr2d2]

4) Can I also say "your mouth will begin to bleed" or "the bleeding will start from your mouth" instead of "you’ll begin to bleed from your mouth"?

To me, the problem with the wording "The bleeding will start..." is that it presupposes that we already know about bleeding, our only question is where it will start from. The original is giving us completely new information: "You'll begin to bleed." Then it tells us the source of the bleeding: "from your mouth."

So I guess "The bleeding will start..." is not appropriate to use in the context of post #1.

Do you not think it this way?

I'm confused. Your Q4 in the first quote box above suggested that you wanted to use one of those two sentences instead of the original. I told you which one could be used. You're now saying that one of the sentences you proposed (the one I said was OK) can't be used. Are you asking us or telling us?

I can see where you're coming from about the use of the article but I don't feel the problem you see exists. The first sentence ends with a warning "... if you do get bit [sic] by one, you'll feel it immediately". Right there is the presupposition you refer to. It tells you something bad's going to happen so if the next sentence starts "The bleeding will start ...", that's fine. The fact that until that point you didn't know specifically that bleeding was one of the bad things that would happen is irrelevant.