Aver, Avert & Evert

Aver is to affirm positively; to declare, to proclaim: “Yes, the witness did aver that he had seen the suspect at the scene of the crime.”
Avert is to turn aside, to turn away: “She had to avert her head so we could not see her face.”
It also means to prevent, to turn away: “The quick arrival of fire-fighters would avert a major forest fire.”
Evert, on the other hand, means to turn outward or inside out, as any saclike object: “The doctor had to evert her eyelid so he could remove the irritating grain of sand.”