Rule reminder
Not all Italian words follow the regular prefix/suffix patterns. Some look regular but have different meanings or spellings. Always verify: 'spettacolare' is NOT s- + pettacolare (no such root); 'impossibile' is regular; 'improbabile' is regular. Learn exceptions through exposure.
Is 'sperabile' (from sperare) a real Italian word meaning 'to be hoped for'?