如果冲量为零, 则动量不变.If the impulse is zero, there is no change in momentum.正周相动力冲量的定义可以用类似的式子表示.The positive phase dynamic impulse can be defined by a similar expression.用于碰撞过程的动量定理——冲量定理.The momentum theorem applied to an imp...
It is usual to tip waiters, porters, guides and drivers.给服务员、行李搬运工、导游和司机小费是惯例。Is one allowed to offer gratuities to the guides?可以给导游小费 吗 ?Our guides belay us.我们的响导把我们系在绳子的一端....
She flicked a crumb off the corner of her mouth.她擦掉嘴角的面包屑。Micky is a crumb , and he treats me like dirt.米基真令人讨厌,他把我当无赖对待.At last Andrew gave them a crumb of information.最后，安德鲁向他们透露了一点信息。She flicked a crumb off the corner...
人体骨架是由依靠韧带连接的形状相异的骨头构成。The skeleton consists of differently shaped bones held together by ligaments.他膝关节韧带拉伤了。He suffered torn ligaments in his knee.我的韧带撕裂了。I've torn a ligament....
Five per cent of children stammer at some point.5%的儿童在某个时期会口吃。A speech-therapist cured his stammer.一位言语矫治师治愈了他的口吃。He turned white and began to stammer.他脸色发白，说话开始结巴。...
The Emperor must realize that he has us at his mercy.皇帝必须意识到我们任由他处置。Ordinary people are at the mercy of faceless bureaucrats.普通人的命运任凭那些平庸刻板的官僚们摆布。They meant to finish her off, swiftly and without mercy.他们打算毫不留情地迅速结果了她。...
Such as grain sheet rubber, it play the role of derrick and inflaming retarding.如有纹理的橡胶片, 这种材料可起到防滑、阻燃等功能.There may be a need for retarding growth chemically to keep trees within bounds.可能需要用化学剂抑制生长,使树冠保持在一定的范围内.This inv...