题目

—Is the pencil box on the floor? —Yes, ______. A．it isn't                   B．it is                         C．they are                 D．they aren't 答案：B“劝君莫打三春鸟，儿在巢中盼母归”这句诗体现鸟所处的时期是（　　）A．交配期B．育雏期C．产卵期D．孵化期