Lava Glasslike obsidian is formed when lava ... Igneous Rock Igneous rock is the primary rock of the Earth&#39;s crust.
(Lava Glasslike obsidian; is formed; T:when lava ... Igneous Rock Igneous rock is the primary rock of the Earth&#39) (Igneous Rock Igneous rock; is; the primary rock of the Earth&#39) (Igneous rock; [is] Rock [of]; Igneous)
Lava Glasslike obsidian Igneous Rock Igneous rock Igneous rock
is formed is [is] Rock [of]
T:when lava ... Igneous Rock Igneous rock is the primary rock of the Earth&#39
the primary rock of the Earth&#39
Igneous