{"id":18181,"date":"2026-08-01T09:02:59","date_gmt":"2026-08-01T02:02:59","guid":{"rendered":"https:\/\/smartcom.vn\/blog\/?p=18181"},"modified":"2026-08-01T09:02:59","modified_gmt":"2026-08-01T02:02:59","slug":"once-in-a-blue-moon","status":"publish","type":"post","link":"https:\/\/smartcom.vn\/blog\/once-in-a-blue-moon\/","title":{"rendered":"Once In A Blue Moon"},"content":{"rendered":"\n\n
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\n 5\/5 - (1 b\u00ecnh ch\u1ecdn) <\/div>\n <\/div>\n

Once in a blue moon l\u00e0 m\u1ed9t th\u00e0nh ng\u1eef (idiom) ti\u1ebfng Anh v\u00f4 c\u00f9ng ph\u1ed5 bi\u1ebfn, mang \u00fd ngh\u0129a l\u00e0 “c\u1ef1c k\u1ef3 hi\u1ebfm khi”, “r\u1ea5t hi\u1ebfm khi” ho\u1eb7c “n\u0103m th\u00ec m\u01b0\u1eddi h\u1ecda” m\u1edbi x\u1ea3y ra m\u1ed9t l\u1ea7n. C\u1ee5m t\u1eeb n\u00e0y b\u1eaft ngu\u1ed3n t\u1eeb hi\u1ec7n t\u01b0\u1ee3ng thi\u00ean v\u0103n k\u1ef3 th\u00fa c\u00f9ng t\u00ean (khi Tr\u0103ng tr\u00f2n xu\u1ea5t hi\u1ec7n l\u1ea7n th\u1ee9 2 trong c\u00f9ng m\u1ed9t th\u00e1ng d\u01b0\u01a1ng l\u1ecbch), d\u00f9ng \u0111\u1ec3 ch\u1ec9 nh\u1eefng s\u1ef1 vi\u1ec7c c\u00f3 x\u00e1c su\u1ea5t di\u1ec5n ra v\u00f4 c\u00f9ng th\u1ea5p trong \u0111\u1eddi s\u1ed1ng.<\/em><\/p>\n

Tuy nhi\u00ean, trong c\u00e1c b\u00e0i thi n\u00f3i v\u00e0 vi\u1ebft nh\u01b0 IELTS hay giao ti\u1ebfp th\u1ef1c t\u1ebf, vi\u1ec7c ch\u1ec9 bi\u1ebft ngh\u0129a th\u00f4i l\u00e0 ch\u01b0a \u0111\u1ee7 m\u00e0 b\u1ea1n c\u1ea7n ph\u1ea3i bi\u1ebft c\u00e1ch ph\u1ed1i h\u1ee3p t\u1eeb v\u00e0 \u0111\u1eb7t v\u00e0o \u0111\u00fang ng\u1eef c\u1ea3nh \u0111\u1ec3 di\u1ec5n \u0111\u1ea1t t\u1ef1 nhi\u00ean nh\u1ea5t.<\/em><\/p>\n

B\u00e0i vi\u1ebft n\u00e0y s\u1ebd gi\u1ea3i \u0111\u00e1p chi ti\u1ebft Once in a blue moon<\/strong><\/span><\/a> l\u00e0 g\u00ec, ngu\u1ed3n g\u1ed1c th\u00fa v\u1ecb \u0111\u1eb1ng sau th\u00e0nh ng\u1eef n\u00e0y, c\u00e1c c\u1ea5u tr\u00fac \u0111\u1eb7t c\u00e2u chu\u1ea9n x\u00e1c, c\u00f9ng danh s\u00e1ch c\u00e1c t\u1eeb \u0111\u1ed3ng ngh\u0129a\/tr\u00e1i ngh\u0129a \u0111\u1eaft gi\u00e1 gi\u00fap b\u1ea1n “n\u00e2ng c\u1ea5p” v\u1ed1n t\u1eeb v\u1ef1ng c\u1ee7a m\u00ecnh ngay l\u1eadp t\u1ee9c!<\/em><\/p>\n

<\/span>Once in a blue moon l\u00e0 g\u00ec?<\/span><\/span><\/h2>\n

Trong ti\u1ebfng Anh, <\/span>once in a blue moon<\/b> l\u00e0 m\u1ed9t th\u00e0nh ng\u1eef (idiom) c\u1ef1c k\u1ef3 ph\u1ed5 bi\u1ebfn, \u0111\u00f3ng vai tr\u00f2 l\u00e0 m\u1ed9t tr\u1ea1ng t\u1eeb ch\u1ec9 t\u1ea7n su\u1ea5t (adverb of frequency) trong c\u00e2u.<\/span><\/p>\n

D\u1ecbch m\u1ed9t c\u00e1ch th\u00f4 ngh\u0129a \u0111en, c\u1ee5m t\u1eeb n\u00e0y c\u00f3 ngh\u0129a l\u00e0 <\/span>“m\u1ed9t l\u1ea7n v\u00e0o d\u1ecbp tr\u0103ng xanh”<\/span><\/i>. Tuy nhi\u00ean, ng\u01b0\u1eddi b\u1ea3n x\u1ee9 kh\u00f4ng bao gi\u1edd d\u00f9ng n\u00f3 \u0111\u1ec3 t\u1ea3 m\u00e0u s\u1eafc c\u1ee7a m\u1eb7t tr\u0103ng.<\/span><\/p>\n

V\u1ec1 m\u1eb7t ngh\u0129a b\u00f3ng, <\/span>once in a blue moon<\/b> mang \u00fd ngh\u0129a l\u00e0: <\/span>r\u1ea5t hi\u1ebfm khi, n\u0103m th\u00ec m\u01b0\u1eddi h\u1ecda, h\u1ecda ho\u1eb1n l\u1eafm m\u1edbi x\u1ea3y ra<\/b> (very rarely, almost never).<\/span><\/p>\n

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  • V\u00ed d\u1ee5:<\/span><\/i> My brother lives in Canada, so we only see him <\/span>once in a blue moon<\/b>. (Anh trai t\u1edb s\u1ed1ng \u1edf Canada, n\u00ean n\u0103m th\u00ec m\u01b0\u1eddi h\u1ecda c\u1ea3 nh\u00e0 m\u1edbi \u0111\u01b0\u1ee3c g\u1eb7p anh \u1ea5y m\u1ed9t l\u1ea7n.)<\/span><\/li>\n<\/ul>\n

    \u0110\u1ed1i v\u1edbi c\u00e1c b\u1ea1n h\u1ecdc sinh, sinh vi\u00ean \u0111ang \u00f4n luy\u1ec7n ti\u1ebfng Anh, vi\u1ec7c thay th\u1ebf c\u00e1c t\u1eeb ch\u1ec9 t\u1ea7n su\u1ea5t c\u01a1 b\u1ea3n b\u1eb1ng c\u1ee5m idiom n\u00e0y s\u1ebd gi\u00fap c\u00e2u v\u0103n c\u00f3 “mu\u1ed1i” h\u01a1n, \u0111\u1ed3ng th\u1eddi ghi \u0111i\u1ec3m tuy\u1ec7t \u0111\u1ed1i v\u1ec1 \u0111\u1ed9 t\u1ef1 nhi\u00ean (nativeness).<\/span><\/p>\n

    \"once<\/p>\n

    <\/span>Ngu\u00f4\u0300n g\u00f4\u0301c va\u0300 c\u00e1ch s\u1eed d\u1ee5ng Once in a blue moon<\/span><\/span><\/h2>\n

    <\/span>1. Ngu\u1ed3n g\u1ed1c ly k\u1ef3 t\u1eeb hi\u1ec7n t\u01b0\u1ee3ng thi\u00ean v\u0103n<\/span><\/span><\/h3>\n

    T\u1ea1i sao l\u1ea1i l\u00e0 “tr\u0103ng xanh” (blue moon) m\u00e0 kh\u00f4ng ph\u1ea3i tr\u0103ng v\u00e0ng hay tr\u0103ng \u0111\u1ecf? Tr\u00ean th\u1ef1c t\u1ebf, M\u1eb7t Tr\u0103ng kh\u00f4ng th\u1ef1c s\u1ef1 chuy\u1ec3n sang m\u00e0u xanh d\u01b0\u01a1ng.<\/span><\/p>\n

    Thu\u1eadt ng\u1eef “Blue Moon” trong ng\u00e0nh thi\u00ean v\u0103n h\u1ecdc d\u00f9ng \u0111\u1ec3 ch\u1ec9 hi\u1ec7n t\u01b0\u1ee3ng tr\u0103ng tr\u00f2n l\u1ea7n th\u1ee9 hai trong c\u00f9ng m\u1ed9t th\u00e1ng d\u01b0\u01a1ng l\u1ecbch (m\u1ed9t \u0111i\u1ec1u r\u1ea5t hi\u1ebfm g\u1eb7p, th\u01b0\u1eddng ph\u1ea3i m\u1ea5t kho\u1ea3ng 2,7 n\u0103m m\u1edbi c\u00f3 m\u1ed9t l\u1ea7n). Do t\u00ednh ch\u1ea5t “hi\u1ebfm c\u00f3 kh\u00f3 t\u00ecm” n\u00e0y, t\u1eeb th\u1ebf k\u1ef7 19, ng\u01b0\u1eddi d\u00e2n c\u00e1c n\u01b0\u1edbc n\u00f3i ti\u1ebfng Anh \u0111\u00e3 b\u1eaft \u0111\u1ea7u s\u1eed d\u1ee5ng c\u1ee5m t\u1eeb <\/span>once in a blue moon<\/b> nh\u01b0 m\u1ed9t ph\u00e9p \u1ea9n d\u1ee5 cho b\u1ea5t k\u1ef3 s\u1ef1 ki\u1ec7n n\u00e0o c\u1ef1c k\u1ef3 \u00edt khi x\u1ea3y ra trong \u0111\u1eddi s\u1ed1ng.<\/span><\/p>\n

    <\/span>2. C\u00e1ch s\u1eed d\u1ee5ng chu\u1ea9n ng\u1eef ph\u00e1p trong ti\u1ebfng Anh<\/span><\/span><\/h3>\n

    V\u00ec \u0111\u00f3ng vai tr\u00f2 nh\u01b0 m\u1ed9t tr\u1ea1ng t\u1eeb ch\u1ec9 t\u1ea7n su\u1ea5t, v\u1ecb tr\u00ed c\u1ee7a c\u1ee5m t\u1eeb n\u00e0y trong c\u00e2u r\u1ea5t linh ho\u1ea1t. B\u1ea1n c\u00f3 th\u1ec3 \u0111\u1eb7t n\u00f3 \u1edf <\/span>cu\u1ed1i c\u00e2u<\/b> (ph\u1ed5 bi\u1ebfn nh\u1ea5t) ho\u1eb7c <\/span>\u0111\u1ea7u c\u00e2u<\/b> \u0111\u1ec3 nh\u1ea5n m\u1ea1nh.<\/span><\/p>\n

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    • C\u1ea5u tr\u00fac ph\u1ed5 bi\u1ebfn:<\/b> S + V + (O) + once in a blue moon<\/span><\/li>\n
    • V\u00ed d\u1ee5:<\/span><\/i> I go to the gym <\/span>once in a blue moon<\/b>; I prefer working out at home. (H\u1ecda ho\u1eb1n l\u1eafm t\u1edb m\u1edbi ra ph\u00f2ng gym; t\u1edb th\u00edch t\u1ef1 t\u1eadp \u1edf nh\u00e0 h\u01a1n.)<\/span><\/li>\n
    • \u0110\u1eb7t \u1edf \u0111\u1ea7u c\u00e2u (T\u1ea1o \u0111i\u1ec3m nh\u1ea5n):<\/b> Once in a blue moon, S + V + (O)<\/span><\/li>\n
    • V\u00ed d\u1ee5:<\/span><\/i> Once in a blue moon<\/b>, our strict teacher lets us leave class 10 minutes early. (N\u0103m th\u00ec m\u01b0\u1eddi h\u1ecda, gi\u00e1o vi\u00ean nghi\u00eam kh\u1eafc c\u1ee7a ch\u00fang t\u1edb m\u1edbi cho c\u1ea3 l\u1edbp v\u1ec1 s\u1edbm 10 ph\u00fat.)<\/span><\/li>\n<\/ul>\n

      \"ngu\u1ed3n<\/p>\n

      <\/span>Ca\u0301c c\u1ee5m t\u1eeb li\u00ean quan v\u1edbi Once in a blue moon<\/span><\/span><\/h2>\n

      \u0110\u1ec3 kh\u00f4ng b\u1ecb l\u1eb7p t\u1eeb trong c\u00e1c b\u00e0i vi\u1ebft lu\u1eadn (Writing) ho\u1eb7c b\u00e0i n\u00f3i (Speaking), vi\u1ec7c l\u00e0m gi\u00e0u v\u1ed1n t\u1eeb b\u1eb1ng c\u00e1c t\u1eeb \u0111\u1ed3ng ngh\u0129a v\u00e0 c\u1ee5m t\u1eeb li\u00ean quan l\u00e0 v\u00f4 c\u00f9ng quan tr\u1ecdng. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 b\u1ea3ng t\u1ed5ng h\u1ee3p c\u00e1c “v\u0169 kh\u00ed” thay th\u1ebf h\u1ea1ng n\u1eb7ng gi\u00fap b\u1ea1n \u0111a d\u1ea1ng h\u00f3a c\u00e1ch di\u1ec5n \u0111\u1ea1t:<\/span><\/p>\n\n\n\n\n\n\n\n\n\n
      C\u1ee5m t\u1eeb \/ T\u1eeb v\u1ef1ng<\/strong><\/td>\n\u00dd ngh\u0129a<\/strong><\/td>\nNg\u1eef c\u1ea3nh s\u1eed d\u1ee5ng<\/strong><\/td>\n<\/tr>\n
      Very rarely<\/span><\/td>\nR\u1ea5t hi\u1ebfm khi<\/span><\/td>\nD\u00f9ng trong m\u1ecdi ng\u1eef c\u1ea3nh (Giao ti\u1ebfp & H\u1ecdc thu\u1eadt)<\/span><\/td>\n<\/tr>\n
      Seldom<\/span><\/td>\n\u00cdt khi, hi\u1ebfm khi<\/span><\/td>\nMang t\u00ednh trang tr\u1ecdng (Formal) h\u01a1n “rarely”<\/span><\/td>\n<\/tr>\n
      Hardly ever \/ Almost never<\/span><\/td>\nH\u1ea7u nh\u01b0 kh\u00f4ng bao gi\u1edd<\/span><\/td>\nC\u1ef1c k\u1ef3 ph\u1ed5 bi\u1ebfn trong giao ti\u1ebfp h\u1eb1ng ng\u00e0y c\u1ee7a gi\u1edbi tr\u1ebb<\/span><\/td>\n<\/tr>\n
      Scarcely<\/span><\/td>\nHi\u1ebfm khi, v\u1eeba v\u1eb7n<\/span><\/td>\nTh\u01b0\u1eddng d\u00f9ng trong v\u0103n vi\u1ebft, c\u1ea5u tr\u00fac \u0111\u1ea3o ng\u1eef<\/span><\/td>\n<\/tr>\n
      Once in a lifetime<\/span><\/td>\nC\u01a1 h\u1ed9i duy nh\u1ea5t trong \u0111\u1eddi<\/span><\/td>\nNh\u1ea5n m\u1ea1nh t\u1ea7m quan tr\u1ecdng, t\u00ednh ch\u1ea5t qu\u00fd gi\u00e1 c\u1ee7a s\u1ef1 ki\u1ec7n<\/span><\/td>\n<\/tr>\n
      From time to time<\/span><\/td>\nTh\u1ec9nh tho\u1ea3ng (T\u1ea7n su\u1ea5t cao h\u01a1n blue moon)<\/span><\/td>\nKhi mu\u1ed1n n\u00f3i v\u1ec1 h\u00e0nh \u0111\u1ed9ng l\u1eb7p l\u1ea1i nh\u01b0ng kh\u00f4ng \u0111\u1ec1u \u0111\u1eb7n<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

      <\/span>Once in a blue moon trong ng\u1eef c\u1ea3nh th\u1ef1c t\u1ebf<\/span><\/span><\/h2>\n

      Th\u00e0nh ng\u1eef n\u00e0y c\u00f3 t\u00ednh \u1ee9ng d\u1ee5ng c\u1ef1c cao. H\u00e3y xem ng\u01b0\u1eddi b\u1ea3n x\u1ee9 \u0111\u01b0a c\u1ee5m t\u1eeb n\u00e0y v\u00e0o \u0111\u1eddi s\u1ed1ng v\u00e0 ph\u00f2ng thi IELTS nh\u01b0 th\u1ebf n\u00e0o nh\u00e9!<\/span><\/p>\n

      <\/span>1. Trong giao ti\u1ebfp h\u1eb1ng ng\u00e0y (Daily Conversation)<\/span><\/span><\/h3>\n

      Gen Z th\u01b0\u1eddng d\u00f9ng c\u1ee5m t\u1eeb n\u00e0y \u0111\u1ec3 “t\u1ef1 luy\u1ebfn” ho\u1eb7c than th\u1edf v\u1ec1 c\u00e1c th\u00f3i quen l\u00e0nh m\u1ea1nh c\u1ee7a m\u00ecnh:<\/span><\/p>\n

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      • H\u1ed9i tho\u1ea1i:<\/span><\/i>\n
          \n
        • A: “Do you cook your own meals?” (C\u1eadu c\u00f3 t\u1ef1 n\u1ea5u \u0103n kh\u00f4ng?)<\/span><\/li>\n
        • B: “Nah, <\/span>once in a blue moon<\/b>. I\u2019m a loyal customer of food delivery apps.” (Th\u00f4i xin, n\u0103m th\u00ec m\u01b0\u1eddi h\u1ecda m\u1edbi n\u1ea5u. T\u1edb l\u00e0 kh\u00e1ch h\u00e0ng trung th\u00e0nh c\u1ee7a m\u1ea5y app \u0111\u1eb7t \u0111\u1ed3 \u0103n r\u1ed3i.)<\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

          <\/span>2. Trong b\u00e0i thi IELTS Speaking (\u0110\u1eb7c bi\u1ec7t l\u00e0 Part 1)<\/span><\/span><\/h3>\n

          Khi g\u1eb7p c\u00e1c c\u00e2u h\u1ecfi d\u1ea1ng <\/span>“How often do you…”<\/span><\/i> (B\u1ea1n c\u00f3 th\u01b0\u1eddng xuy\u00ean l\u00e0m g\u00ec \u0111\u00f3 kh\u00f4ng?), thay v\u00ec tr\u1ea3 l\u1eddi <\/span>“No, I don’t”<\/span><\/i>, h\u00e3y \u00e1p d\u1ee5ng ngay c\u00f4ng th\u1ee9c ghi \u0111i\u1ec3m Lexical Resource d\u01b0\u1edbi \u0111\u00e2y:<\/span><\/p>\n

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          • Question:<\/b> How often do you visit museums?<\/span><\/li>\n
          • Sample Answer:<\/b> “To be perfectly honest, I only visit museums <\/span>once in a blue moon<\/b>. Since my schedule at university is always jam-packed with assignments, I barely have any spare time for cultural exhibitions. I think the last time I set foot in a museum was two years ago.”<\/span><\/li>\n
          • B\u1ea3n d\u1ecbch:<\/span><\/i> Th\u00e0nh th\u1eadt m\u00e0 n\u00f3i, h\u1ecda ho\u1eb1n l\u1eafm t\u00f4i m\u1edbi \u0111i b\u1ea3o t\u00e0ng. V\u00ec l\u1ecbch h\u1ecdc \u1edf tr\u01b0\u1eddng \u0111\u1ea1i h\u1ecdc lu\u00f4n ng\u1eadp \u0111\u1ea7u trong b\u00e0i t\u1eadp, t\u00f4i h\u1ea7u nh\u01b0 kh\u00f4ng c\u00f3 th\u1eddi gian r\u1ea3nh cho c\u00e1c cu\u1ed9c tri\u1ec3n l\u00e3m v\u0103n h\u00f3a. T\u00f4i ngh\u0129 l\u1ea7n cu\u1ed1i c\u00f9ng m\u00ecnh \u0111\u1eb7t ch\u00e2n \u0111\u1ebfn b\u1ea3o t\u00e0ng l\u00e0 t\u1eeb hai n\u0103m tr\u01b0\u1edbc r\u1ed3i.<\/span><\/li>\n<\/ul>\n

            \"once<\/p>\n

            <\/span>B\u00e0i t\u1eadp v\u1ec1 Once in a blue moon co\u0301 \u0111a\u0301p a\u0301n<\/span><\/span><\/h2>\n

            H\u00e3y c\u00f9ng “test” nhanh xem b\u1ea1n \u0111\u00e3 n\u1eb1m l\u00f2ng c\u00e1ch d\u00f9ng c\u1ee7a th\u00e0nh ng\u1eef <\/span>once in a blue moon l\u00e0 g\u00ec<\/b> th\u00f4ng qua 5 c\u00e2u b\u00e0i t\u1eadp th\u1ef1c h\u00e0nh d\u01b0\u1edbi \u0111\u00e2y.<\/span><\/p>\n

            C\u00e2u 1:<\/b> Choose the word that has a SIMILAR meaning to the underlined phrase:<\/span><\/p>\n

            “We go out for a fancy dinner <\/span><\/i>once in a blue moon<\/i><\/b> because it is too expensive.”<\/span><\/i><\/p>\n

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            1. frequently<\/span><\/li>\n
            2. very rarely<\/span><\/li>\n
            3. daily<\/span><\/li>\n
            4. punctually<\/span><\/li>\n<\/ol>\n

              C\u00e2u 2:<\/b> Complete the sentence: <\/span>“Since they broke up, they talk to each other only ________.”<\/span><\/i><\/p>\n

                \n
              1. once in a blue moon<\/span><\/li>\n
              2. back and forth<\/span><\/li>\n
              3. day in, day out<\/span><\/li>\n
              4. now and then<\/span><\/li>\n<\/ol>\n

                C\u00e2u 3:<\/b> Which of the following sentences is grammatically CORRECT?<\/span><\/p>\n

                  \n
                1. Once a blue moon in, I travel abroad.<\/span><\/li>\n
                2. I once in a blue moon see my childhood friends.<\/span><\/li>\n
                3. He watches horror movies once in a blue moon.<\/span><\/li>\n
                4. My dad forgets my mom’s birthday once in a blue moon time.<\/span><\/li>\n<\/ol>\n

                  C\u00e2u 4:<\/b> \u0110i\u1ec1n t\u1eeb c\u00f2n thi\u1ebfu v\u00e0o ch\u1ed7 tr\u1ed1ng \u0111\u1ec3 ho\u00e0n th\u00e0nh th\u00e0nh ng\u1eef: <\/span>“Once in a _______ moon.”<\/span><\/i><\/p>\n

                    \n
                  1. red<\/span><\/li>\n
                  2. full<\/span><\/li>\n
                  3. new<\/span><\/li>\n
                  4. blue<\/span><\/li>\n<\/ol>\n

                    C\u00e2u 5:<\/b> D\u1ecbch c\u00e2u sau sang ti\u1ebfng Anh c\u00f3 s\u1eed d\u1ee5ng c\u1ee5m t\u1eeb \u0111\u00e3 h\u1ecdc: <\/span>“H\u1ed3i c\u00f2n \u1edf k\u00fd t\u00fac x\u00e1, n\u0103m th\u00ec m\u01b0\u1eddi h\u1ecda t\u00f4i m\u1edbi th\u1ee9c d\u1eady s\u1edbm.”<\/span><\/i><\/p>\n

                      \n
                    1. When living in the dorm, I woke up early everyday.<\/span><\/li>\n
                    2. When living in the dorm, I only woke up early once in a blue moon.<\/span><\/li>\n
                    3. When living in the dorm, I went back and forth early.<\/span><\/li>\n
                    4. When living in the dorm, I rarely wake up early.<\/span><\/li>\n<\/ol>\n

                      \u0110\u00e1p \u00e1n chi ti\u1ebft:<\/span><\/p>\n

                        \n
                      1. B<\/b> (Very rarely \u0111\u1ed3ng ngh\u0129a v\u1edbi once in a blue moon).<\/span><\/li>\n
                      2. A<\/b> (Ng\u1eef c\u1ea3nh chia tay n\u00ean r\u1ea5t hi\u1ebfm khi n\u00f3i chuy\u1ec7n l\u1ea1i).<\/span><\/li>\n
                      3. C<\/b> (\u0110\u1eb7t c\u1ee5m t\u1eeb \u1edf cu\u1ed1i c\u00e2u \u0111\u00fang c\u1ea5u tr\u00fac ng\u1eef ph\u00e1p).<\/span><\/li>\n
                      4. D<\/b> (Blue moon l\u00e0 t\u1eeb c\u1ed1 \u0111\u1ecbnh c\u1ee7a th\u00e0nh ng\u1eef n\u00e0y).<\/span><\/li>\n
                      5. B<\/b> (D\u1ecbch chu\u1ea9n ngh\u0129a v\u00e0 \u0111\u00fang th\u00ec qu\u00e1 kh\u1ee9 \u0111\u01a1n “woke up”).<\/span><\/li>\n<\/ol>\n

                        <\/span>T\u1ed5ng k\u1ebft<\/span><\/span><\/h2>\n

                        T\u00f3m l\u1ea1i, hi\u1ec3u \u0111\u01b0\u1ee3c <\/span>once in a blue moon l\u00e0 g\u00ec<\/b> kh\u00f4ng ch\u1ec9 gi\u00fap b\u1ea1n gi\u1ea3i m\u00e3 \u0111\u01b0\u1ee3c m\u1ed9t c\u1ee5m t\u1eeb ti\u1ebfng Anh th\u00fa v\u1ecb m\u00e0 c\u00f2n gi\u00fap “\u0111\u1ed5i gi\u00f3” cho c\u00e1ch n\u00f3i, c\u00e1ch vi\u1ebft c\u1ee7a m\u00ecnh b\u1edbt r\u1eadp khu\u00f4n. Nh\u1eefng idiom \u0111\u1eaft gi\u00e1 nh\u01b0 th\u1ebf n\u00e0y ch\u00ednh l\u00e0 “ch\u1ea5t x\u00fac t\u00e1c” gi\u00fap b\u00e0i n\u00f3i IELTS c\u1ee7a b\u1ea1n nghe T\u00e2y h\u01a1n, m\u01b0\u1ee3t m\u00e0 h\u01a1n v\u00e0 d\u1ec5 d\u00e0ng h\u1ea1 g\u1ee5c nh\u1eefng v\u1ecb gi\u00e1m kh\u1ea3o kh\u00f3 t\u00ednh nh\u1ea5t.<\/span><\/p>\n

                        Tuy nhi\u00ean, ghi nh\u1edb t\u1eeb v\u1ef1ng m\u1edbi ch\u1ec9 l\u00e0 b\u01b0\u1edbc kh\u1edfi \u0111\u1ea7u. \u0110\u1ec3 th\u1ef1c s\u1ef1 bi\u1ebfn nh\u1eefng c\u1ee5m t\u1eeb n\u00e0y th\u00e0nh ph\u1ea3n x\u1ea1 t\u1ef1 nhi\u00ean \u2013 b\u1eadt ra ngay l\u1eadp t\u1ee9c trong ph\u00f2ng thi m\u00e0 kh\u00f4ng c\u1ea7n m\u1ea5t th\u1eddi gian suy ngh\u0129 3-4 gi\u00e2y \u2013 b\u1ea1n c\u1ea7n m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p h\u1ecdc chu\u1ea9n khoa h\u1ecdc v\u00e0 m\u1ed9t ng\u01b0\u1eddi th\u1ea7y \u0111\u1ed3ng h\u00e0nh \u0111\u1ecbnh h\u01b0\u1edbng.<\/span><\/p>\n

                        \ud83d\udc49 <\/span>B\u1ea1n l\u00e0 h\u1ecdc sinh c\u1ea5p 3 \u0111ang loay hoay v\u1edbi m\u1ee5c ti\u00eau k\u1ecbp c\u00f3 b\u1eb1ng IELTS x\u00e9t tuy\u1ec3n \u0111\u1ea1i h\u1ecdc th\u1eb3ng?<\/b><\/p>\n

                        \ud83d\udc49 <\/span>B\u1ea1n l\u00e0 sinh vi\u00ean \u0111ang “m\u1ea5t g\u1ed1c” ti\u1ebfng Anh, s\u1ee3 k\u1ef9 n\u0103ng Speaking v\u00e0 c\u1ea7n m\u1ed9t b\u1ec7 ph\u00f3ng \u0111\u1ec3 \u0111\u1ea1t m\u1ed1c 6.5+ ra tr\u01b0\u1eddng?<\/b><\/p>\n

                        \u0110\u1eebng \u0111\u1ec3 ti\u1ebfng Anh l\u00e0 r\u00e0o c\u1ea3n t\u01b0\u01a1ng lai c\u1ee7a b\u1ea1n! H\u00e3y click ngay v\u00e0o <\/span>[Form \u0110\u0103ng K\u00fd T\u01b0 V\u1ea5n & Ki\u1ec3m Tra Tr\u00ecnh \u0110\u1ed9 Mi\u1ec5n Ph\u00ed]<\/b> t\u1ea1i \u0111\u00e2y. Ch\u1ec9 v\u1edbi 15 ph\u00fat test ph\u1ea3n x\u1ea1 c\u00f9ng chuy\u00ean gia, b\u1ea1n s\u1ebd nh\u1eadn ngay m\u1ed9t l\u1ed9 tr\u00ecnh h\u1ecdc c\u00e1 nh\u00e2n h\u00f3a “may \u0111o” ri\u00eang cho Gen Z, gi\u00fap b\u1ea1n t\u0103ng t\u1eeb 1 – 1.5 band Speaking ch\u1ec9 sau m\u1ed9t kh\u00f3a h\u1ecdc ng\u1eafn h\u1ea1n. \u0110\u0103ng k\u00fd h\u00f4m nay \u0111\u1ec3 gi\u1eef su\u1ea5t \u01b0u \u0111\u00e3i h\u1ecdc b\u1ed5ng l\u00ean t\u1edbi 30% nh\u00e9!<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

                        Once in a blue moon l\u00e0 m\u1ed9t th\u00e0nh ng\u1eef (idiom) ti\u1ebfng Anh v\u00f4 c\u00f9ng ph\u1ed5 bi\u1ebfn, mang \u00fd ngh\u0129a l\u00e0 “c\u1ef1c k\u1ef3 hi\u1ebfm khi”, “r\u1ea5t hi\u1ebfm khi” ho\u1eb7c “n\u0103m th\u00ec m\u01b0\u1eddi h\u1ecda” m\u1edbi x\u1ea3y ra m\u1ed9t l\u1ea7n. C\u1ee5m t\u1eeb n\u00e0y b\u1eaft ngu\u1ed3n t\u1eeb hi\u1ec7n t\u01b0\u1ee3ng thi\u00ean v\u0103n k\u1ef3 th\u00fa c\u00f9ng t\u00ean (khi Tr\u0103ng tr\u00f2n xu\u1ea5t […]<\/p>\n","protected":false},"author":20,"featured_media":18193,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-18181","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tin-tuc-ielts"],"yoast_head":"\nOnce in a blue moon l\u00e0 g\u00ec | Ngu\u1ed3n g\u1ed1c v\u00e0 c\u00e1ch d\u00f9ng<\/title>\n<meta name=\"description\" content=\"Once in a blue moon l\u00e0 g\u00ec? \u0110\u00e2y l\u00e0 m\u1ed9t idiom trong ti\u1ebfng Anh r\u1ea5t th\u00f4ng d\u1ee5ng, nh\u01b0ng kh\u00f4ng ph\u1ea3i ai c\u0169ng n\u1eafm \u0111\u01b0\u1ee3c ngh\u0129a c\u1ee7a n\u00f3. 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M\u1ee5c ti\u00eau l\u1edbn nh\u1ea5t c\u1ee7a Smartcom Team l\u00e0 x\u00e2y d\u1ef1ng m\u1ed9t th\u1ebf h\u1ec7 tr\u1ebb t\u1ef1 tin, l\u00e0m ch\u1ee7 ng\u00f4n ng\u1eef v\u00e0 s\u1eb5n s\u00e0ng v\u01b0\u01a1n ra th\u1ebf gi\u1edbi.","sameAs":["https:\/\/www.facebook.com\/anhduc.smartcom\/","https:\/\/www.linkedin.com\/in\/nguyenanhduc8112\/","https:\/\/x.com\/uc_anh40675","https:\/\/www.youtube.com\/@smartcomvn"],"url":"https:\/\/smartcom.vn\/blog\/author\/smartcom-english\/"}]}},"_links":{"self":[{"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/posts\/18181","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/users\/20"}],"replies":[{"embeddable":true,"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/comments?post=18181"}],"version-history":[{"count":2,"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/posts\/18181\/revisions"}],"predecessor-version":[{"id":18197,"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/posts\/18181\/revisions\/18197"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/media\/18193"}],"wp:attachment":[{"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/media?parent=18181"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/categories?post=18181"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/smartcom.vn\/blog\/wp-json\/wp\/v2\/tags?post=18181"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}