One tile: across the entire width

[4x2]

Two tiles: 2x2 next to each other

[2x2][2x2]

Three tiles: one 2x1, next to it two 1x1 next to each other

[2x1][1x1][1x1]

Three tiles: two 1x1 next to each other, one 2x1 next to it

[1x1][1x1][2x1]