{
"id": "string",
"role": "string",
"content": "string",
"audio_duration": 0,
"pronunciation_score": 0,
"fluency_score": 0,
"grammar_score": 0,
"relevance_score": 0,
"feedback": "string",
"created_at": "2019-08-24T14:15:22.123Z"
}