Two.
A parallelogram has four sides, and looks like a rectangle that's been squashed over. It thus retains the property that each side is parallel to the one opposite it.
A diamond has two pairs of parallel lines.
A rhombus has 2 pairs of parallel lines.
A regular dodecagon has six pairs of parallel lines.
it has 2 pairs of parallel lines
it has too parallel lines!
A pentagon has no parallel lines.
A parallelogram is, conventionally, a four sided figure with two sets of parallel sides and four interior angles. Some people argue that hexagons (with three pairs of parallel lines), octagons (4 pairs) and, generally, 2n-gons with n pairs of parallel sides should also be considered parallelograms.
A regular octagon has four pairs of parallel lines.
A square has 2 pairs of equal opposite parallel lines
A parallelogram has 2 pairs of parallel lines
A square has 2 pairs of parallel lines and they all are the same lenght
A nonagon is a nine-sided polygon. In a nonagon, there are four pairs of parallel lines. This is because the nonagon can be divided into three sets of parallel lines, each containing three parallel lines. Each set of parallel lines consists of three pairs of parallel lines.