胚胎的性别早在受精时就决定了。The sex of the embryo is predetermined at fertilization.收集母牛胚胎的方法有两种, 一种是直接通过产道, 另一种是施用外科手术.There are two methods of collecting cow embryos -- directly through the birth canal, or surgically.目的: 探索制作小鼠多倍体胚...
The area where most refugees are waiting is exposed to the elements.大多数难民等待救济的地方都不能挡风遮雨。"I have never knowingly exposed any patient to needless risks," he said.他说：“我从未故意将任何病人置于不必要的风险境地。”He has simply been exposed as an a...
The candidates are already limbering up for the election campaign.各候选人已经在为竞选运动热身了.We start by doing limbering up exercises and then go on to do the aerobics.我们先做些柔软运动灵活四肢,再做有氧运动....
I was wrong about it being a casual meeting.我误以为这是个非正式会议。A sharp dresser, Wyatt is never seen in casual clothes.怀亚特衣着入时，从未有人见过他穿便装。Garland tried to appear casual, but he couldn't conquer his unease.加兰努力装出无所谓的样子，可是他没...