Turning point of a graph is the point where the graph where the graph changes from increasing to decreasing (rising to falling) or decreasing to increasing (falling to rising). For a cubic function, the critical point also serves as a turning point.
The italicized word or phrase <em>a three-pronged </em>(if this is italicized, we cannot possibly know) is attributive, as it is an adjective to describe the plan.
Your family is a dependent clause as well as Venice. :)
