1. Useful to show where words have been left out, either from the middle or the end of a sentence:

'Once a jolly swagman camped ... down came a jumbuck...' (note spacing)

2. May be used to indicate indecision or hesitation, the tailing off of a sentence, or to represent a pregnant pause—particularly useful when transcribing:

And that must have been a happy time, or...

Oh, very happy...well, maybe not completely... (note spacing)

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