经济学人下载: 眼前的黑不是黑(3)

音频下载[点击右键另存为]

Both groups share two attributes normally associated with vertebrates.

两组都具有通常脊椎动物才具备的两个特征。

2. light up 照亮；发亮

Many shooting stars light up the sky.

许多流星照亮了天空。