"by day" meaning in 英語

{
  "categories": [
    {
      "kind": "other",
      "name": "有1個詞條的頁面",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "英語介詞短語",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "英語詞元",
      "parents": [],
      "source": "w"
    }
  ],
  "lang": "英語",
  "lang_code": "en",
  "pos": "prep_phrase",
  "related": [
    {
      "word": "by night"
    }
  ],
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "有使用例的英語詞",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "He is a policeman by day and a thief by night.",
          "translation": "他白天做警察，晚上當小偷。"
        }
      ],
      "glosses": [
        "在白天"
      ],
      "id": "zh-by_day-en-prep_phrase-ZIvhfN0A"
    }
  ],
  "word": "by day"
}

{
  "categories": [
    "有1個詞條的頁面",
    "英語介詞短語",
    "英語詞元"
  ],
  "lang": "英語",
  "lang_code": "en",
  "pos": "prep_phrase",
  "related": [
    {
      "word": "by night"
    }
  ],
  "senses": [
    {
      "categories": [
        "有使用例的英語詞"
      ],
      "examples": [
        {
          "text": "He is a policeman by day and a thief by night.",
          "translation": "他白天做警察，晚上當小偷。"
        }
      ],
      "glosses": [
        "在白天"
      ]
    }
  ],
  "word": "by day"
}