观鸟俱乐部的成员们正在研究不同种类的鸟以及它们数量上的变化。

The members of the Birdwatching Club are studying the different kinds of birds and the changes in their numbers.

youdao

观鸟俱乐部的成员们正在研究不同种类的鸟以及它们数量上的变化。

The members of the Birdwatching Club are studying the different kinds of birds and the changes in their numbers.

youdao