"teach Grandma how to suck eggs" meaning in English

{
  "forms": [
    {
      "form": "teaches Grandma how to suck eggs",
      "tags": [
        "present",
        "singular",
        "third-person"
      ]
    },
    {
      "form": "teaching Grandma how to suck eggs",
      "tags": [
        "participle",
        "present"
      ]
    },
    {
      "form": "taught Grandma how to suck eggs",
      "tags": [
        "participle",
        "past"
      ]
    },
    {
      "form": "taught Grandma how to suck eggs",
      "tags": [
        "past"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "teach<,,taught> Grandma how to suck eggs"
      },
      "expansion": "teach Grandma how to suck eggs (third-person singular simple present teaches Grandma how to suck eggs, present participle teaching Grandma how to suck eggs, simple past and past participle taught Grandma how to suck eggs)",
      "name": "en-verb"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "alt_of": [
        {
          "word": "teach grandma how to suck eggs"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
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          "source": "w"
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        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
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      "examples": [
        {
          "ref": "1956 May, P. B. M. Allan, “Larval Foodplants”, in B. R. Stallwood, editor, The Bulletin of the Amateur Entomologists’ Society, volume 15, number 185, London: The Amateur Entomologists’ Society […], page 38, column 2:",
          "text": "Every man who attended those Sunday lunches at the old Fox and Hounds inn at Darenth in the ’seventies and ’eighties could have told one of these things about almost every common British lepidopteron. How they would have laughed at such a book as Larval Foo[d]plants! “Teaching Grandma how to suck eggs” would have been the general verdict upon it.",
          "type": "quote"
        },
        {
          "ref": "1977, Gerald Forsberg, “Stricken vessels. Ocean towage”, in Salvage from the Sea, London; Henley-on-Thames, Oxfordshire: Routledge and Kegan Paul, →ISBN, page 67:",
          "text": "Let’s assume that a rocket or gun line has got to the right position in the casualty. It is a slim weak line in itself and something more substantial is required quickly. First then a heaving line or a point line is attached and hauled across. When that, still smallish, line is in hand a medium sized rope is attached in turn and that is hauled across. Only then can the casualty hope to heave over the actual tow-wire from the tug. The last action is to see that the tow-wire is thoroughly and securely made fast. That sounds like teaching Grandma how to suck eggs but even experienced seamen can fail to appreciate the enormous stresses involved.",
          "type": "quote"
        },
        {
          "ref": "2004, Claudia Carroll, chapter 22, in He Loves Me Not . . . He Loves Me, London: Bantam Books, published 2005, →ISBN, page 335:",
          "text": "‘There’s nothing like a challenge, as I tell all my paramours,’ he’d cheerfully said to Jimmy D. earlier in the day, ‘but I think I’ll need a good two hours before she’s camera ready. And, please don’t think I’m teaching Grandma how to suck eggs here, but you might wanna think about using a lot of soft focus in this scene.’",
          "type": "quote"
        }
      ],
      "glosses": [
        "Alternative letter-case form of teach grandma how to suck eggs."
      ],
      "id": "en-teach_Grandma_how_to_suck_eggs-en-verb-c52jMAEq",
      "links": [
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          "teach grandma how to suck eggs",
          "teach grandma how to suck eggs#English"
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      "tags": [
        "alt-of"
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    }
  ],
  "word": "teach Grandma how to suck eggs"
}

{
  "forms": [
    {
      "form": "teaches Grandma how to suck eggs",
      "tags": [
        "present",
        "singular",
        "third-person"
      ]
    },
    {
      "form": "teaching Grandma how to suck eggs",
      "tags": [
        "participle",
        "present"
      ]
    },
    {
      "form": "taught Grandma how to suck eggs",
      "tags": [
        "participle",
        "past"
      ]
    },
    {
      "form": "taught Grandma how to suck eggs",
      "tags": [
        "past"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "teach<,,taught> Grandma how to suck eggs"
      },
      "expansion": "teach Grandma how to suck eggs (third-person singular simple present teaches Grandma how to suck eggs, present participle teaching Grandma how to suck eggs, simple past and past participle taught Grandma how to suck eggs)",
      "name": "en-verb"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "alt_of": [
        {
          "word": "teach grandma how to suck eggs"
        }
      ],
      "categories": [
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        "English lemmas",
        "English multiword terms",
        "English terms with quotations",
        "English verbs",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "examples": [
        {
          "ref": "1956 May, P. B. M. Allan, “Larval Foodplants”, in B. R. Stallwood, editor, The Bulletin of the Amateur Entomologists’ Society, volume 15, number 185, London: The Amateur Entomologists’ Society […], page 38, column 2:",
          "text": "Every man who attended those Sunday lunches at the old Fox and Hounds inn at Darenth in the ’seventies and ’eighties could have told one of these things about almost every common British lepidopteron. How they would have laughed at such a book as Larval Foo[d]plants! “Teaching Grandma how to suck eggs” would have been the general verdict upon it.",
          "type": "quote"
        },
        {
          "ref": "1977, Gerald Forsberg, “Stricken vessels. Ocean towage”, in Salvage from the Sea, London; Henley-on-Thames, Oxfordshire: Routledge and Kegan Paul, →ISBN, page 67:",
          "text": "Let’s assume that a rocket or gun line has got to the right position in the casualty. It is a slim weak line in itself and something more substantial is required quickly. First then a heaving line or a point line is attached and hauled across. When that, still smallish, line is in hand a medium sized rope is attached in turn and that is hauled across. Only then can the casualty hope to heave over the actual tow-wire from the tug. The last action is to see that the tow-wire is thoroughly and securely made fast. That sounds like teaching Grandma how to suck eggs but even experienced seamen can fail to appreciate the enormous stresses involved.",
          "type": "quote"
        },
        {
          "ref": "2004, Claudia Carroll, chapter 22, in He Loves Me Not . . . He Loves Me, London: Bantam Books, published 2005, →ISBN, page 335:",
          "text": "‘There’s nothing like a challenge, as I tell all my paramours,’ he’d cheerfully said to Jimmy D. earlier in the day, ‘but I think I’ll need a good two hours before she’s camera ready. And, please don’t think I’m teaching Grandma how to suck eggs here, but you might wanna think about using a lot of soft focus in this scene.’",
          "type": "quote"
        }
      ],
      "glosses": [
        "Alternative letter-case form of teach grandma how to suck eggs."
      ],
      "links": [
        [
          "teach grandma how to suck eggs",
          "teach grandma how to suck eggs#English"
        ]
      ],
      "tags": [
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  ],
  "word": "teach Grandma how to suck eggs"
}