Once a shape passed swiftly a few feet overhead.
She was just starting to doze off when a shape passed through the glass door.
Its black shape passed a few feet to the side, visible only as a moving shadow.
The scientist looked up as a dark shape passed far overhead and circled.
A vast winged shape passed over the moon like a black cloud.
No shape passed across the strip of half light showing between the drapes.
A grey shape passed across her vision, came back, peered down.
They moved at a great speed, but he saw that similar dark shapes occasionally passed in the region of the upper air.
A dark shape passed overhead, further away from shore.
A dark shape sometimes passes across the sky, only seen by blotting out the stars as it goes.