'********** comparison 'If robin is a type of bird then usually robin is a type of animal. < bird> ==> animal>>. %0.70% 'If robin can fly then robin is a type of animal. < [flying]> ==> animal>>. 19 'I guess robin is a type of bird if and only if robin can fly. ''outputMustContain('< [flying]> <=> bird>>. %0.70;0.45%')