Signs for EXTENSIVE
Depending on the contexts or subjects in sentence, these are some possibilities.
Meaning: spreading over a large area; large in spatial extent or range or scope or quantity.
E.g. "extended farm lands".
Meaning: great in amount, number, or degree.
E.g. "a large city; "a large family".
Meaning: comprehensive; far-reaching or thorough; involving a lot of details and information.
E.g.: "an extensive knowledge of Deaf studies", "linguists have conducted research into the linguistics of sign language.
Meaning: Of great extent; wide; broad; covering a large area; having a great range.