His tub lost its balance; Bill somersaulted backward into the water.
His ship flipped over backward, rolling on its long axis as it somersaulted.
Out it came, and in the meshes flopped and tumbled and somersaulted three tiny fish.
Then one of them fell away, somersaulted, tumbled down wildly—out of control.
The gash was behind and above my right ear, so I must have somersaulted ...