Common Noun:
* When "heap" refers to a general pile or accumulation of things, it's a common noun.
* Example: "There was a heap of leaves in the yard."
Collective Noun:
* When "heap" refers to a group or collection of individual items considered as a unit, it's a collective noun.
* Example: "The heap of coins was worth a fortune."
Let's analyze the examples:
* "Heap of leaves": Here, "heap" describes the shape of the leaves, making it a common noun.
* "Heap of coins": Here, "heap" refers to the collection of coins as a single entity, making it a collective noun.
Therefore, "heap" can be either a common or collective noun depending on its usage and the context of the sentence.