This means that the semFA function returns a configuration with the empty statement sequence, the initial environment, and the empty stack.
Then the control returns to the last choice point, so the function semFA is called recursively with a statement sequence taken from the top of the stack and the environment taken from the top of the stack, updated with the changes resulting from the computation of T.
If the recursive call of semFA fails, then the whole computation fails.
This completes the description of semFA. To link the semFA function with the sem function we distinguish two cases.