清晨的花园里充满了悦耳的鸟鸣声。

The morning garden was alive with cheerful ___birdcalls.

这位观鸟爱好者擅长模仿各种鸟鸣声来吸引鸟儿靠近。

The birdwatcher is skilled at making realistic ___birdcalls to draw birds closer.