Answer
See below:
Work Step by Step
When the input of the function $f\left( x \right)$ changes to $f\left( x+a \right)$ the graph of the function $f\left( x \right)$ is shifted to the left by $a$ units.
Again, if the function $f\left( x \right)$ is changed to $f\left( x \right)+b$ the graph of the function $f\left( x \right)$ is shifted up by $b$ units.
The above graph has a maximum value of 4 at $-2$.
The graph is never zero since it does not cross or touch the x-axis.