VectorPlot[{-1,1},{x,-2,2},{y,-2,2}]

VectorPlot[{x,y},{x,-2,2},{y,-2,2}]

VectorPlot[{2*y,0},{x,-2,2},{y,-2,2}]

VectorPlot[{-y,x},{x,-2,2},{y,-2,2}]

VectorPlot3D[{x,0,0},{x,-2,2},{y,-2,2},{z,-2,2},VectorScale->Medium]

VectorPlot3D[{y,-x,z},{x,-2,2},{y,-2,2},{z,-2,2},VectorScale->Medium]

VectorPlot3D[{2,1,-3},{x,-2,2},{y,-2,2},{z,-2,2},VectorScale->Medium]

VectorPlot3D[{-x,-y,-z},{x,-2,2},{y,-2,2},{z,-2,2},VectorScale->Medium]