Example:

"Your favours nor your hate.
Hail!
Hail!
Hail!
Lesser than Macbeth and greater."
(Act 1, Scene 3, Lines 61-65).

Explanation:

Not only is the word "hail!" repeated, but the fact that it is repeated three times is significant. It is so that each side of the audience could be addressed (front and two sides). It has also been noted that the number three is an unlucky number.