Assertion: platypus's spine | /r/HasProperty | sharp
Facets:
Source sentences:
text: The male platypus has a sharp spine on his two back legs called ankle spurs which contain a poison.
text: The male platypus has a sharp spine on his two back ankles called spurs which contain a venom.
text: The male platypus has a sharp spine on his two back legs called ankle spurs which contain a poison.