The definition for comparable is "Similar, equivalent." Used in a sentence: Helen will only accept something of comparable value for her ticket to the concert.

The definition for derelict is "Abandoned." Used in a sentence: The derelict house was condemned as a public hazard.

The definition for naive is "Lacking worldy wisdom." Used in a sentence: The naive Simon assumed that everyone was as simple and kind as he was.

The definition for periodic is "Occurring at regular intervals." Used in a sentence: The periodic innterruptions of the cuckoo clock prevented Li from concentrating.

The definition for placebo is "An inactive substance used in medical testing." Used in a sentence: Tom, who had taken the placebo, found that his allergy symptoms did not go away.