... cetaceans, or marine (1) : they breathe air, they are warm-blood, and they bear live young ones called (2) .The size of dolphins vary greatly. The smallest dolphin is just about 50 kg in weight and 1.2 ... professionals. Football, or (1) is an example of a professional game. The game of football was first (2) In Britain and then spread (3) other countries. Now all countries hope to compete for the World...