［週末閒情］慎防有讀者太後生唔知係乜，呢個係我將件西多切成七巧板後再砌出嚟的。作為一個前數學老師當然知道七巧板點切，同埋點砌東西。

TL：DR—平行四邊形呢塊真係好特別的

1. 有次我咁玩，對面個小朋友睇到好入神，想有樣學樣，結果畀佢老母粗暴地阻止咗。所以唔使問點解香港冇STEM，如果阿媽冇三層樓留畀你的話（＊）都係專心drink water溫dictation，女嘅嫁人，男嘅大個做ibanker啦（＊＊）

2. 知唔知七巧板英文叫乜？原來都幾騎呢，叫做Tangram．但Tan唔係七喎，咁係乜？其實都冇人知！相當肯定嘅係，七巧板係中國傳去歐洲嘅，所以有人話個Tan係唐人（＊＊＊），我相信都係。至於有話Tan for 蜑家我就覺得太有想像力了

3. 又，講數學時間啦，七巧板固然就係七塊，但寧舍有一塊係最特別嘅，知唔知邊塊？就係平行四邊形（＊＊＊＊）嗰塊。

4. 點解？你話，「得一塊嘛」。錯，得一塊唔足以叫做特別，正如每個人都唔同但唔係每個人都特別。況且，其實中三角（有大中小三角嘛，大三角有兩塊，小三角都係兩塊，中三角得一塊）同埋正方形都係得一塊。但平行四邊形呢塊係寧舍唔同的。

5. 點解？開估。無論你砌任何嘢都好，只有平行四邊形呢塊，係有需要反轉！其他嗰六塊你當然「可以」反，但係冇必要的，只係證明你水皮，或者好得閒。但平行四邊形呢塊，唔反的話，有啲圖係砌唔到的！

6. 又點解會咁？好簡單。小學有教，對稱。平行四邊形嗰塊，係唯一一塊唔對稱嘅（知咩叫對稱架可？）。亦即係話，另外六塊，個鏡像mirror image，都係可俄羅斯方塊咁rotate出嚟的。唯獨係平行四邊形，mirror image係另一樣嘢，你要反轉件西多先砌到。「其實讀化學都讀呢啲嘢」

7. 所以，平行四邊形呢塊，搵手反轉砌完（我講西多，唔係條仔）影相，就質比條仔食啦。其他嘅唔使反的，轉嚟轉去得了。

8. 同埋，記住砌之前唔好落糖漿。因為要反轉。你見我都冇落。唔好以為唔使反可以砌晒任何嘢。

9. 呀當然，任何情況你都唔應該落煉奶。

10. 點解讀書年代阿Sir唔會教呢啲？好簡單，講呢啲「歐思」，學生唔屌家長都實屌。所以唔使問點解香港冇STEM

11. 呀，其實我有個願望，希望搵次拎Wendy’s塊方形漢堡扒嚟砌。不過啲刀工應該要好啲先得，或者搵埃汾太幫手。因為我會手震（所以冇讀醫）

（＊）一層炒一層住一層收租，香港核心價值

（＊＊）不過其實我老豆都係咁上下，當年我好多問題問，佢都係叫我唔好問咁多問題去打機好過。嘻。倒係我老母就會滿足下我呢個問題兒童

（＊＊＊）雖然七巧板應該係宋朝先出現，但唐人唐山呢啲稱呼一早有

（＊＊＊＊）嚴格嚟講呢，「所有正方形都係平行四邊形」（你知架可？唔知就再證明香港嘅STEM得啖笑）。「所以其實正方形嗰塊都係平行四邊形」。不過做人唔好咁煩，大家明啦下，呢度「平行四邊形」係指「唔係正方形嗰塊平行四邊形」。（＊＊＊＊＊）

（＊＊＊＊＊）In case真係有人唔知，煩請你去查下乜嘢叫「正方形」乜嘢叫「平行四邊形」。咁你就會知道，正方形係菱形（！！！）嘅一種特例，而菱形係平行四邊形嘅一種特例。亦即係正方形係菱形嘅subset，菱形係平行四邊形嘅subset．或者話，所有正方形都係菱形（但唔係所有菱形都係正方形），而所有菱形都係平行四邊形（但唔係所有平行四邊形都係菱形）—「拿，我已經用咗三種方法解，係咪好清楚呢」。認真，其實睇定義就明晒。教數學時呢，見到啲小聰明嘅學生（十居其九係男仔），玩到呢啲就全部收晒皮。心算叻冇乜用嘅，數學嘅嘢最緊要play by the rules．「所以不如討論下咩叫做平行四邊形」

（＊＊＊＊＊＊）講真的，我懷疑十個有九個大學生都講唔出乜嘢係菱形（Rhombus/Diamond）．咁你睇定義，四條邊等長嘅四邊形就係菱形。但，亦都代表所有菱形就必然係平行四邊形。The proof is left as an exercise to the reader

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原價 US$ 1.99 益智動物七巧板《 Tayasui Tangram 》限時免費
下載 https://buff.ly/2VPau8v

原價 US$ 1.99 益智動物七巧板《 Tayasui Tangram 》限時免費
下載 https://bit.ly/2wXq0qe

七巧板由個正方形分成七個唔同形狀嘅板拼合而成，可以砌到好多唔同嘅圖案，可以能鍛煉孩子的動手能力，還能開發孩子的想像力。

Tangram puzzle consist seven separated flat shapes which could be combined together to form different other shapes, letter, animal...etc.

Tangrams are very fun and educational for kids, it allow kid to grow the creativity and problems solving skills.

This video is also suitable for someone who want to learn English as second language, We hope your kid will enjoy this video and learn the pronunciation and name of farm same as my kid.
If you want to watch more video from us, please
-do subscribe us!
http://www.youtube.com/channel/UC7pL7...

-like the video and share to you friend who have kid on the facebook, tweeter, google+....etc

Learn names of animal with sound playlist:
https://www.youtube.com/playlist?list...


Learn names of street vehicle and its sound playlist
https://www.youtube.com/playlist?list...

Learn names of fruits and vegetables
https://www.youtube.com/playlist?list...

Learn number and counting playlist:
https://www.youtube.com/playlist?list...

七巧板由個正方形分成七個唔同形狀嘅板拼合而成，可以砌到好多唔同嘅圖案，可以能鍛煉孩子的動手能力，還能開發孩子的想像力。

Tangram puzzle consist seven separated flat shapes which could be combined together to form different other shapes, letter, animal...etc.

Tangrams are very fun and educational for kids, it allow kid to grow the creativity and problems solving skills.

This video is also suitable for someone who want to learn English as second language, We hope your kid will enjoy this video and learn the pronunciation and name of farm same as my kid.
If you want to watch more video from us, please
-do subscribe us!
http://www.youtube.com/channel/UC7pL7...

-like the video and share to you friend who have kid on the facebook, tweeter, google+....etc

Learn names of animal with sound playlist:
https://www.youtube.com/playlist?list...


Learn names of street vehicle and its sound playlist
https://www.youtube.com/playlist?list...

Learn names of fruits and vegetables
https://www.youtube.com/playlist?list...

Learn number and counting playlist:
https://www.youtube.com/playlist?list...

七巧板由個正方形分成七個唔同形狀嘅板拼合而成，可以砌到好多唔同嘅圖案，可以能鍛煉孩子的動手能力，還能開發孩子的想像力。

Tangram puzzle consist seven separated flat shapes which could be combined together to form different other shapes, letter, animal...etc.

Tangrams are very fun and educational for kids, it allow kid to grow the creativity and problems solving skills.

This video is also suitable for someone who want to learn English as second language, We hope your kid will enjoy this video and learn the pronunciation and name of farm same as my kid.
If you want to watch more video from us, please
-do subscribe us!
http://www.youtube.com/channel/UC7pL7...

-like the video and share to you friend who have kid on the facebook, tweeter, google+....etc

Learn names of animal with sound playlist:
https://www.youtube.com/playlist?list...


Learn names of street vehicle and its sound playlist
https://www.youtube.com/playlist?list...

Learn names of fruits and vegetables
https://www.youtube.com/playlist?list...

Learn number and counting playlist:
https://www.youtube.com/playlist?list...