These rocks were folded and metamorphosed when the Appalachian Mountains were formed during the Appalachian Revolution, some 270 million years ago.
(These rocks; were folded; ) (These rocks; metamorphosed; T:when the Appalachian Mountains were formed during the Appalachian Revolution, some 270 million years ago) (the Appalachian Mountains; were formed; T:during the Appalachian Revolution; T:some 270 million years ago)
These rocks These rocks the Appalachian Mountains
were folded metamorphosed were formed
T:when the Appalachian Mountains were formed during the Appalachian Revolution, some 270 million years ago
T:during the Appalachian Revolution T:some 270 million years ago