Assertion: trampoline's surface | /r/MadeOf | canvas
Facets:
value: usually
type: TEMPORAL
Source sentences:
text: Typical packages, when purchased straight from the box, will include the jumping surface, usually made of canvas; the spring cover, which is a pad that goes around the outside of the trampoline to cover the springs and prevent injuries; an enclosure, which goes around the trampoline, about 5 feet tall, made to prevent children from falling off the trampoline; and a top rail that is padded to prevent injuries to the head.