"a" meaning in Tok Pisin

{
  "etymology_text": "Imitative or onomatopoeia.",
  "head_templates": [
    {
      "args": {
        "1": "tpi",
        "2": "interjections"
      },
      "expansion": "a",
      "name": "head"
    }
  ],
  "lang": "Tok Pisin",
  "lang_code": "tpi",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 179 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Tok Pisin entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "english": "→New International Version translation",
          "ref": "1989, Buk Baibel long Tok Pisin, Port Moresby: Bible Society of Papua New Guinea, Jenesis 3:1:",
          "text": "God, Bikpela i bin wokim olgeta animal, tasol i no gat wanpela bilong ol inap winim snek long tok gris. Na snek i askim meri olsem, “Ating God i tambuim yutupela long kaikai pikinini bilong olgeta diwai bilong gaden, a?”",
          "type": "quote"
        }
      ],
      "glosses": [
        "eh?"
      ],
      "id": "en-a-tpi-intj-4m7nMfuV",
      "links": [
        [
          "eh",
          "eh"
        ]
      ]
    }
  ],
  "word": "a"
}

{
  "etymology_text": "Imitative or onomatopoeia.",
  "head_templates": [
    {
      "args": {
        "1": "tpi",
        "2": "interjections"
      },
      "expansion": "a",
      "name": "head"
    }
  ],
  "lang": "Tok Pisin",
  "lang_code": "tpi",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        "Pages with 179 entries",
        "Pages with entries",
        "Tok Pisin entries with incorrect language header",
        "Tok Pisin interjections",
        "Tok Pisin lemmas",
        "Tok Pisin terms with quotations"
      ],
      "examples": [
        {
          "english": "→New International Version translation",
          "ref": "1989, Buk Baibel long Tok Pisin, Port Moresby: Bible Society of Papua New Guinea, Jenesis 3:1:",
          "text": "God, Bikpela i bin wokim olgeta animal, tasol i no gat wanpela bilong ol inap winim snek long tok gris. Na snek i askim meri olsem, “Ating God i tambuim yutupela long kaikai pikinini bilong olgeta diwai bilong gaden, a?”",
          "type": "quote"
        }
      ],
      "glosses": [
        "eh?"
      ],
      "links": [
        [
          "eh",
          "eh"
        ]
      ]
    }
  ],
  "word": "a"
}