vacant line
常見(jiàn)例句
- A plausible reason is that all the dinosaurs had been killed off, except the line that evolved into birds, and the placental mammals speciated into the ecological niches that had been left vacant.
一個(gè)可能的原因是所有恐龍除進(jìn)化爲(wèi)鳥(niǎo)的一支外都死掉了，胎磐類哺乳動(dòng)物才在被空閑出來(lái)的生態(tài)龕中得以進(jìn)化。 返回 vacant line