The Tawny Eagle is very similar to the Steppe Eagle which is larger and darker coloured.
The gape of the Tawny Eagle is an easy way to distinguish it from the Steppe Eagle.
The gape of the Steppe Eagle extends beyond the centre of the eye whereas the gape of the Tawny Eagle extends back only to the level of the front of the eye.

1st photo: Moremi Game Reserve, Botswana, 21 November 2001
2nd photo: Chobe National Park, Botswana, 17 November 2001