 | The two pairs of adjacent sides are equal. | | |
|  | The two pairs of opposite sides are parallel. | | |
|
 | The two pairs of opposite sides are parallel, and all angles are right angles. | | |
|  | The two pairs of opposite sides are parallel, and all four sides are equal. | | |
|
 | The two pairs of opposite sides are parallel, all sides are congruent, and all angles are right angles. | | |
|  | Only one pair of opposite sides must be parallel. | | |
|
