| 摘要 |
A learning aid is composed of a rectangular support base (1) onto which is rotatably mounted a disc (2). A strip (4) acting as a finger stop radially overlies the disc (2). The disc (2) has a series of spaced finger holes (6) around its periphery through which alphabetic letters (7) on the base (1) are visible as well as a display window (9) to ensure the disc (2) is located correctly relative to the base (1). By inserting a finger into a selected hole (6) and rotating the disc (2) until the finger stop (4) is reached and by co-ordinating the angular displacement of the disc (2) with the display window (9) a user can select and check tasks and solutions. |
