Answer
First blank is $downwards$.
Second blank is $right$.
Work Step by Step
To obtain the graph of $2^{x}-1$, a simple vertical translation can be applied one unit downwards so the whole function is shifted down by one unit. This is because the transformation is ''-1'' and not +1 so it is shifted downwards.
On the other hand to obtain the graph of $2^{x-1}$, the graph has to be shifted to the right by one unit since this is a horizontal translation and it is to the right because of the negative sign. The negative indicates a shift to the right while a positive indicates a shift to the left.
