起源

origin; source; birth; beginning; genesis; provenance; root; derivation; appearance; seed; pedigree; originate; derive; stem; rise; arise; start; stem from; -head

不明

unknown; unclear; obscure; indistinct; vague; ambiguous; unexplained; undefined; murky; dim; faint; hazy; nebulous; indeterminate; veiled; dark; dull; fuzzy; do not understand; be not clear