Prehistoric
Part of speech: adjective
Definition: Of relating to the epoch before written record. Nonmodern.
Example sentence: Through the study of fossils I had already been initiated into the mysteries of prehistoric creations.
Period
Part of speech: adjective
Definition: Appropriate for a given historical era.
Part of speech: interjection
Definition: And nothing else; and nothing less; used for emphasis.
Part of speech: noun
Definition: Punctuation mark “” (indicating the ending of a sentence or marking an abbreviation).A length of time.An epoch, era, time in history or in a person's life.A specific length of time that an activity (such as a game or a school day) is conventionally divided into.The minimum interval during which the same characteristics of a periodic phenomenon recur, such as the repetition of a wave or the rotation of a planet.Female menstruation.A row in the periodic table of the elements.A Drosophila gene which gene product is involved in regulation of the circadian rhythm
Example sentence: Finishing is one of the most difficult things to do in cricket. A player can't be a finisher in just 6 months or one year. You have to be used to that responsibility, keeping on doing what is required from you over a period of time.