All inside corners must be rounded.

内部的角必须是圆形的。

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Birmingham had the best of the early exchanges with three corners inside 11 minutes, but went behind to a flowing Blackburn move.

BBC: CHOOSE A SPORT

Inverness started brightly, winning three corners inside the first six minutes.

BBC: St Mirren 2-0 Inverness CT

Or straight edged pieces that go inside the puzzle, fake corners, no corners, and so on.

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