Explanation : Voice modulation (or varying the speed,
pitch and tone) in teaching is a technique
that keeps the learners' interest fastened on
the teacher and make teaching effective.
On the other hand, slow expression of
words might make fast learners impatient,
presentation without pause may steal
the valuable moments of reflection from
the students, and resorting to semantic
jugglery (play with words) may undermine
comprehension.