Most direct substitution of groups bound to an aromatic nucleus is limited to diazonium salts.大多数连于芳核能被直接取代的基团仅限于重氮盐.Severe steric effects at the reactive carbon would impede the substitution.大的立体效应阻止在碳上的取代.We use saccha...
In my experience a straight substitution of carob for chocolate doesn'twork.根据我的经验，用角豆制品直接代替巧克力行不通。We use saccharin in substitution for sugar.我们用糖精代替糖.Substitution, No.3 for No.4.换人,4号下, 3号上....
She'd learnt to be herself and to stand up for her convictions.她已经学会了按自己的方式行事，坚持自己的信仰。Always stand up for your principles.要一贯坚持你的原则.Girls who have always been at a mixed school know how to stand up for themselves.一直...
He was at his happiest whilst playing cricket.玩板球时他最开心了。Young adolescents are happiest with small groups of close friends.青少年在和自己小圈子里的好友呆在一起时最为开心。She was a studious child, happiest when reading.她是个勤奋好学的孩子, 读书最使她感到快乐.He w...
He began slicing the pie up.他开始把馅饼切片。The wind was slicing off the tops of the waves now.风呼啸而来,象利刃一样切割着波峰浪尖.The dust produced during slicing weighs almost as much as the wafers.在切割时所产生的碎屑几乎和薄片一样重....
星际通信的实际问题不在于技术.The real problem of interstellar communication does not concern technology.事实上, 危及他们通信的机会是很少的.In fact, the chances of compromising their communications were slim.作一次星际通信的认真尝试可能很费钱.A serious attempt at inte...