Uni-/Mono-
speaking one language
What is monolingual
a vehicle with three wheels
What is tricycle
to create four times as much or as many of something
What is quadruple
a group or set of five
What is quintet
a period of 10 years
What is decade
one tone
What is monotone
eyeglasses with lenses that have two different sections
What is bifocals
the ability to speak four languages
What is quadrilingual
a polygon of five angles and five sides
What is pentagon
a period of 100 years
What is century
a series of three books or movies
What is trilogy
an animal having four feet
What is quadruped
one of five offspring born at the same time
What is quintuplets
subdivided into tenths
What is decimal
a group or set of four
What is quartet
perfectly typical or representative of a particular kind of thing; originally comes from 'fifth element'
What is quintessential
a 200th anniversary or its celebration
What is becentennial
a longer speech performed by one actor
What is monologue
a chord of three tones
What is triad
a four sided enclosure, usually surrounded by buildings
What is quadrangle
an athletic contest involving participation in five different events
What is pentathlon
a part of a whole expressed in hundredths
What is percentage