* Formal: The twins were indistinguishable from each other, even to their parents.
* Descriptive: The fake painting was indistinguishable from the original, fooling even the most experienced art critic.
* Figurative: After spending the entire day in the sun, her skin was indistinguishable from a lobster's.
* Comparative: The taste of the store-bought cookies was indistinguishable from homemade.
* Negative: The suspect's description was so vague that the police found him indistinguishable from dozens of other people in the crowd.
Remember, "indistinguishable" means "impossible to tell apart."