Question

the bold word is a \middle swabi\ (subordinating conjunction). does the highlighted comma belong? black panther will decorate the cake, as long as you bake it.

Explanation:

A "middle SWABI" (subordinating conjunction) connects a dependent clause to an independent clause in the middle of the sentence. When the subordinating conjunction is in the middle, we do not use a comma before it. The independent clause here is "Black Panther will decorate the cake" and the dependent clause is "as long as you bake it". Since "as long as" is a middle SWABI, the comma before it does not belong.

Answer:

The highlighted comma does not belong.