Worksheet on Quadrilaterals - onlinemath4all WORKSHEET ON QUADRILATERALS. 1. A simple closed shape made up of four line segments is called a _____. 2. The sum of the measures of interior angles of a quadrilateral is _____. 3. A parallelogram having all sides equal is called a _____. 4. A quadrilateral having exactly one pair of parallel sides is called a _____.