重复的 、 残留的及低等的构造易于变异.Multiple, rudimentary, and lowly organized structures are variable.微孢子虫作为一类专营细胞内寄生的低等的原生动物, 有着比较悠久的进化历史.Microsporidia are parasitic protozoa, and have a relative long evolution history.许多地位低等的凡人视其为惺惺作...
September is here, bringing with it a chill in the mornings.9月到了,早晨已有了寒意.The South African mailboat arrived on Friday mornings unless bad weather intervened.除非受恶劣天气干扰，南非邮船一般在星期五上午抵达。In the mornings the sky appeared a hea...