```json
[
{"adjective": "cheap", "comparative": "cheaper", "superlative": "the cheapest"},
{"adjective": "expensive", "comparative": "more expensive", "superlative": "the most expensive"},
{"adjective": "good", "comparative": "better", "superlative": "the best"},
{"adjective": "happy", "comparative": "happier", "superlative": "the happiest"},
{"adjective": "interesting", "comparative": "more interesting", "superlative": "the most interesting"}
]
```