This is possible because language is not the only symbolic means of communication. In order to prove that chimpanzees and gorillas are capable of language, and not simply a different kind of symbolic communication system, they must learn a sign language with the basic characteristics of human language.
Definition of Halloween. : October 31 observed especially with dressing up in disguise, trick-or-treating, and displaying jack-o'-lanterns during the evening.
October 31 marks the observation of Halloween or Halloweâen, a short variation of All-hallow-even, the evening before All Hallows Day or All Saints Day, on November 1. After the Romans conquered the Celts in 43AD, they adopted many of their festivals and incorporated them into their own religious celebrations.