# Grammar metrics

Below are the detailed feedback metrics appearing in the response for `grammar` along with their descriptions, are as follows. 

These metrics are returned by including `include_ielts_feedback = 1` parameter in the [Spontaneous Speech API](/api-reference/score-speech-open-ended.md).

<table data-full-width="false"><thead><tr><th width="411">Parameter</th><th>Description</th></tr></thead><tbody><tr><td>grammar.overall_metrics.length</td><td>The sufficiency of the response length in words to demonstrate the necessary grammatical range.</td></tr><tr><td>grammar.overall_metrics.lexical_diversity</td><td>The degree of variation in syntactic structures such as diversity in verbs, adjectives and adverbial modifiers.</td></tr><tr><td>grammar.overall_metrics.grammatical_accuracy</td><td>The degree of grammatical inaccuracies in the response. A list of grammatical errors with suggested replacements is returned in the <code>grammar.errors</code> node when this index is low.</td></tr><tr><td>grammar.overall_metrics.grammatical_range</td><td><p></p><p>The degree of grammatical range demonstrated in the response. This score is further broken down into 4 additional sub-indices:</p><ul><li>noun_phrase_variation</li><li>noun_phrase_complexity</li><li>verb_construction_variation</li><li>adverb_modifier_variation</li></ul></td></tr><tr><td>grammar.overall_metrics.grammatical_range.noun_phrase_variation</td><td>The degree of variation in structure of noun phrases such as the number and types of modifiers used in the response.</td></tr><tr><td>grammar.overall_metrics.grammatical_range.noun_phrase_complexity</td><td>The degree of complexity of noun phrases such as the richness of adjectives, relative clauses, prepositional phrases, nonfinite elements, determiners, and demonstratives used in the response.</td></tr><tr><td>grammar.overall.metrics.grammatical_range.verb_construction_variation</td><td>The degree of variation in verbal structures such as the number and types of verb structural elements used in the response.</td></tr><tr><td>grammar.overall.metrics.grammatical_range.adverb_modifier_variation</td><td>The degree of variation in types of adverbs or adverb phrases to modify clauses, verbs, and adjectives used in the response.</td></tr></tbody></table>

An example of `grammar` feedback metrics looks like below:

{% code overflow="wrap" lineNumbers="true" fullWidth="false" %}

```json
{   
"grammar": 
  {
    "overall_metrics": {
      "length": {
         "score": 4,
         "level": "mid"
       },
       "lexical_diversity": {
          "score": 8,
          "level": "high"
       },
       "grammatical_accuracy": {
           "score": 8,
           "level": "high"
        },
        "grammatical_range": {
            "score": 5,
            "level": "mid",
            "message": "Your response has less grammatical range than most advanced speakers. To improve, you should use a wider range of phrasal and clausal structures and verb-argument constructions.",
            "noun_phrase_complexity": {
               "score": 1,
               "level": "low",
               "message": "Your response lacks noun phrase complexity. You should use richer modifiers in noun phrases by using adjectives, relative clauses, prepositional phrases, non-finite elements, determiners, and demonstratives."
            },
            "noun_phrase_variation": {
                "score": 5,
                "level": "mid"
            },
            "verb_construction_variation": {
                "score": 6,
                "level": "mid"
             },
             "adverb_modifier_variation": {
                 "score": 9,
                 "level": "high"
              }
         }
     },
     "errors": [
      {
         "category": "STYLE",
         "message": "Did you mean 'different from'? 'Different than' is often considered colloquial style.",
         "span": [44,48],
         "matched_text": "than",
         "replacements": ["from"]
      }
     ]
 }
}
```

{% endcode %}

#### **Grammatical Error**

The `grammar.errors` node contains a JSON array of grammatical errors found in the response. Each array element is an object with the following properties:

<table data-full-width="false"><thead><tr><th width="157">key</th><th>Description</th></tr></thead><tbody><tr><td>category</td><td>The type of error such as; STYLE, GRAMMAR, COLLOCATION, CONFUSED_WORDS</td></tr><tr><td>message</td><td>A descriptive message of the error. The message may refer to words within the evaluated text and include suggested replacements within the ... markup tags.</td></tr><tr><td>span</td><td>The [begin, end] indices of the matched text in characters.</td></tr><tr><td>matched_text</td><td>The matched text where the error was found.</td></tr><tr><td>replacements</td><td>An array of zero or more suggested replacements where applicable.</td></tr></tbody></table>


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://api-docs.speechace.com/api-reference/score-speech-open-ended/per-metric-feedback/grammar-metrics.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.