The two-dimensional cross sections that could be created by cutting a cube with a plane are:
1. **Square**: A cube can be sliced by a plane to form a square cross section. Each face of a cube is a square, so when a plane intersects the cube, it can produce a square cross section.
2. **Rectangle**: If the plane intersects the cube at a specific angle, it can result in a rectangular cross section. This occurs when the plane cuts through the cube in a way that doesn't align perfectly with the cube's edges.
3. **Triangle**: Cutting a cube with a plane at a specific angle can lead to a triangular cross section. The intersection of the plane and the cube can form a triangle depending on the orientation of the cut.
In summary, a cube can have square, rectangle, and triangular cross sections when intersected by a plane.