正視圖/側視圖/俯視圖 | Front View, Side View and Top View

影片內容：

00:17 – 點解要用平面圖形表達立體圖形? | why 2-D representation of 3-D figures?
00:43 – 繪畫三視圖 | constructing orthographic views of 3-D Figures
02:28 – 從三視圖繪畫立體圖形 | sketching 3-D figures from their orthographic views