Use of 'otherwise'

[99bottles]

These are two sentences I found on Longman.

You’ll have to go now, otherwise you’ll miss your bus.

We were delayed at the airport. Otherwise we would have been here by lunch time.

I noticed that in the first sentence, 'otherwise' is preceded by a comma. In the second sentence, on the other hand, it is preceded by a fullstop. Something else I noticed is that in the second sentence, 'otherwise' is not followed by a comma, although I have a feeling it should. Can someone explain?

 

[Tarheel]

These are two sentences I found on Longman.

You’ll have to go now, otherwise you’ll miss your bus.

We were delayed at the airport. Otherwise we would have been here by lunch time.

I noticed that in the first sentence, 'otherwise' is preceded by a comma. In the second sentence, on the other hand, it is preceded by a fullstop. Something else I noticed is that in the second sentence, 'otherwise' is not followed by a comma, although I have a feeling it should be. Can someone explain?

I would use a period (full stop) in the first instance.

You don't need a comma after "Otherwise".

Added: If you need an explanation you'll have to wait for jutfrank or 5jj.

 

[teechar]

These are two sentences I found on Longman.
You’ll have to go now, otherwise you’ll miss your bus.

I don't concur with that punctuation. I would use "or (else)" in that sentence.

Can someone explain?

To me, "otherwise" functions as a conjunctive adverb, and for an explanation of how those are used, take a look at the following link.
https://writing.wisc.edu/handbook/grammarpunct/conjadv/

 

[jutfrank]

I think the first sentence is fine and punctuated well. The comma represents a natural pause between the two logically connecting clauses. When otherwise is used in this way (see the first entry here), I'd advise always using a comma.

The second sentence employs a different use of otherwise. I understand this conjunctive use as transitional. That means that it introduces a comment about the previous sentence. The comment in this case is an expression of pure condition—you can substitute Otherwise for an entire condition clause (If we hadn't been delayed at the airport). In this function as a transition, I say there really ought to be two separate sentences (a linking semicolon would also suffice) and that it's generally good practice to place a comma after an introductory sentence adverb, just as you would with any other transition.

 

[Phaedrus]

You’ll have to go now, otherwise you’ll miss your bus.

To me, "otherwise" functions as a conjunctive adverb [. . .].

That's my feeling, too. "Otherwise" could actually be preceded by a semicolon and followed by a comma. It could even be placed at the end of the second independent clause, unlike a coordinating conjunction.

You'll have to go now; otherwise, you'll miss your bus.
You'll have to go now; you'll miss your bus, otherwise.

 

[99bottles]

That's my feeling, too. "Otherwise" could actually be preceded by a semicolon and followed by a comma. It could even be placed at the end of the second independent clause, unlike a coordinating conjunction.

You'll have to go now; otherwise, you'll miss your bus.
You'll have to go now; you'll miss your bus, otherwise.

So it needs a comma at the end of the sentence too?

 

[5jj]

I don't think it does.

 

[Tarheel]

Try:

Hurry up or you'll miss your bus.

If for some reason I wanted to force "otherwise" into the sentence I wouldn't put it at the end. (Unless you paid me of course. Then I'll put it anywhere you want. ;-) )