Question

some of the potatoes gone bad has/have​

Answer 1

Answer:

Raw potatoes should be firm to the touch with tight skin that's free of large bruises, black spots, or other blemishes. If a potato has become soft or mushy, you should throw it out. Though it's normal for potatoes to smell earthy or nutty, a musty or moldy odor is a hallmark of spoilage.

Answer 2

Here is your answer...

Some of the potatoes have gone bad.