When the bodies of certain sea animals decayed and were compressed, oil and natural gas were formed.
(the bodies of certain sea animals; decayed; ) (the bodies of certain sea animals; were compressed; ) (oil and natural gas; were formed; T:When the bodies of certain sea animals decayed and were compressed)
the bodies of certain sea animals the bodies of certain sea animals oil and natural gas
decayed were compressed were formed
T:When the bodies of certain sea animals decayed and were compressed