All that remained of a bygone age. 它们是一个过去时代的仅存硕果
a potent cocktail of acid rain poured down. 威力强大的酸雨倾泻而下
A toxic concoction of noxious gases. 一种有毒的混合气体
has been a feature of life on Earth for hundreds of millions of years. 数亿年来 一直是地球生命的特点
A more impressive forerunner to the mammals. 它是哺乳动物更为显赫的前身