```
{
    "english": "I went for a walk in the park yesterday and saw many people exercising there.",
    "important_words": [
        {
            "word_en": "exercise",
            "meaning_ch": "锻炼身体",
            "usage": "usually means physical activity to improve health or fitness"
        },
        {
            "word_en": "public park",
            "meaning_ch": "公园",
            "usage": "a place in a urban area where people can walk or relax"
        }
    ]
}
```