自然种群有三个基本特征，分别为（）、（）和遗传特征。
参考答案：空间特征、数量特征
-----Where is your new home now?
-----In the new developed zone. But I ______ downtown for five years.
A．have lived
B．had lived
C．lived
D．was living
---Can you see some people are waiting _______ the library?
---Yes, They are standing in a queue in front of its gate.
A. around B. inside C. outside
