What is the test for establishing a robbery was committed by means of fear?

"To establish a robbery was committed by means of fear, the prosecution 'must present evidence ". . . that the victim was in fact afraid, and that such fear allowed the crime to be accomplished."' [Citations.]" (People v. Morehead, supra, 191 Cal.App.4th at p. 772.) "It follows . . . that the willful use of fear to retain property immediately after it has been taken from the owner constitutes robbery. So long as the perpetrator uses the victim's fear to accomplish the retention of the property, it makes no difference whether the fear is generated by the perpetrator's specific words or actions designed to frighten, or by the circumstances surrounding the taking itself." (People v. Flynn, supra, 77 Cal.App.4th at p. 772.)