adj.鸭嘴形的
n.鸭嘴兽
New evidence, however, challenges that theory.The duckbill platypus, it turns out, gets about eight hours of REM shuteye a day. 新证据向上述观点提出挑战，它推翻了鸭嘴兽一天睡眠八小时的理论。
