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Penguins are (0) flightless birds which live south of the Equator. As their legs are short, they (56) USUAL stand upright and walk when they are on land. When they find it (57) NEED  to travel at greater speed, they often drop on to their stomachs and slide along. But it is at sea, (58) SPECIAL when diving, that penguins really move fast, the (59) WEIGH of their streamlined bodies allowing them to reach a (60) DEEP of up to 265 metres in some cases
The sixteen species of penguin tend to look rather (61) LIKE with black or dark blue backs and white fronts. But (62) VARY in size and head patterns allow them to be (63) INDENTIFY. The fact that a number of species spend their whole life in Antarctica where there is little (64) PROTECT from the world's least (65) WELCOME weather conditions, makes their continued survival one of the wonders of the nature