Volcanoes

Front

rising in a great wave, a swelling of smoke, ash, and water

Back

billowy

Front

100 years

Back

century

Front

charred bits of rock; ashes

Back

cinders

Front

fallen inward suddenly

Back

collapsed

Front

inactive, but capable of becoming active

Back

dormant

Front

a volcanic explosion or large flow of lava

Back

eruption

Front

no longer active

Back

extinct

Front

made liquid by heat; melted

Back

molten

Front

the top of a mountain

Back

summit

Front

changed because of exposure to the weather

Back

weathered