The Hittite Empire eventually collapsed following invasion from the west by the Achaeans, the Phrygians, and a mysterious force known only as the  Sea People.  
The Hittite Empire finally collapsed due to invasion.
The Hittite empire was finally defeated by the Chinese empire.
Two children playing in the grass.
Professionals will handle the information.
It should not be equal in absolute value.
A couple eat sandwiches together.
Busses, taxis, and rental cars are available methods of thransportation.
The man is pointing at something.