鸟类具有特殊的鸣管肌肉,()目鸟类最为发达。
参考答案:雀形目
检查(母体)尿中的绒毛膜促性腺激素可以辅助诊断早孕。
单项选择。
I have two books. One is for you, ______ is for her. [ ]
A. another
B. other
C. the other