Complex sentence: Unlike the typical hijackings of land vehicles or ships, skyjacking is not usually committed for robbery or theft: most aircraft hijackers intend to use the passengers as hostages, either for monetary ransom or for some political or administrative concession by authorities.
Split into simpler sentences: Unlike the typical hijackings of land vehicles or ships, skyjacking is not usually committed for robbery or theft. Most aircraft hijackers intend to use the passengers as hostages, either for monetary ransom or for some political or administrative concession by authorities.