The boatman refused to row him back.船夫拒绝划船把他送回去。The boatman was willing to risk ferrying them across.船夫愿冒险渡他们过江.The boatman put me across the river.船夫把我渡过了河....
Evolution can explain why human embryos look like gilled fishes.进化论能够解释为什么人类的胚胎看起来象除去了内脏的鱼一样.A sharp demarcation of adventive embryos from zygotic embryos cannot be drawn.不定胚与合子胚之间不能划分出明显的界限.Most grass embryos have a fla...