The object is to trap air in the dough, which expands when heated, creating a rising without yeast.
(The object; is; to trap air in the dough) (The object; to trap; air; in the dough) (the dough; expands; T:when heated)
The object The object the dough
is to trap expands
to trap air in the dough
air in the dough
T:when heated