A third example of how an apparent achievement can, in reality, be a failure is perfectly portrayed in “Romeo and Juliet,” a play by William Shakespeare.

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i think this is about right and yea it sounds pretty good

“A third, example, of how, and achievement, can be, in reality, a failure…”

Is clearly not “right”, and will only distract your reader. It sounds like William Shatner (Captain Kirk from Star Trek) on drugs 😉

But I think that your comma-usage in the example above is perfectly acceptable, and frankly, is exactly how I would have done it.

I think of it like this:

, 1/2 second

; 1 second

: 2 seconds

. 3 seconds.

I know that’s not right, but I get by on it.

If I were writing your sentence I would write it the same way, I think.