In the middle of the room is a tall triangular tunnel that is covered in mirrors.

VOA: special.2009.03.11

The school specializes in Arabic instruments such as the kanoun, a triangular stringed instrument a little like a horizontal harp, and the oud, a pear-shaped stringed instrument similar to a lute, and also teaches Western classical instruments and music theory.

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On a hot Sunday in 1999 three miners find a thin, triangular stone in a muddy Brazilian river.

FORBES: Fracture Lines

India is currently playing a triangular series with Australia and Sri Lanka in Australia after a poor show in the Test series.

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