Another popular gathering place is Plaza de Santisima Trinidad, a semi-circular park built in 1643.

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In its heyday, thousands of people used the swimming pool, semi-circular diving area and changing rooms.

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Many of them work in the squat semi-circular greenhouses of Almeria, their backs bent beneath the plastic roofs, inhaling insecticide.

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The chamber was packed, with the MEPs - including Robert Kilroy-Silk making a very rare appearance, sitting in the non-aligned section with Jean Marie le Pen et al - parked behind their computer screens in semi-circular rows.

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Her leg bones confirm that A. afarensis could walk upright, though her ape-like upper body and the arrangement of the semi-circular canals of her ears, which are the location of the sense of balance, suggest she also spent a lot of time climbing trees.

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Many of the semi-finalists' redesigns are as simple as adding multitouch gestures or bending the traditionally square playing field into a more circular court, but a few ambitious developers mixed it up with 3D playing fields, anthropomorphic paddles or augmented reality multiplayer.

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