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- forward and backward substitution method 前推回代法
- Study on calculating theoretically line loss using forward and backward substitution method 前推回代法计算理论线损研究
- He lined out for home without a backward glance. 他头也不回，急忙往家里走去。
- This part of the country is still backward. 这个国家的这个地区仍很落后。
- In some cities housing conditions went backward. 某些城市的住房条件越来越差。
- The teacher was patient with backward children. 那位老师对迟钝的学童十分耐心。
- We use saccharin in substitution for sugar. 我们用糖精代替糖。
- He looked backward over his shoulder. 他回头向后看。
- She looked backward over her shoulder. 她回头往後看。
- backward substitution 后退代入
- Sheila is very clever but rather backward in expressing her ideas. 希拉很聪明，然而在表达思想时却有些腼腆。
- Although he is clever, he is backward in giving his views. 他虽然很聪明，却不善发表他的意见。
- Frank was so backward that he hesitated to ask her to dance. 法兰克非常腼腆,不好意思请她跳舞。
- He had a firsthand taste of life in backward mountainous areas. 他直接体验过落後山区的生活。
- Substitution of a new obligation for an old one. 更新新契约对旧契约的替代
- The substitution of coal for oil is desirable. 以煤代替石油是可取的。
- A backward flow of water, as from the action of oars. 反流，逆流向后流的水，如由浆的划动引起
- The backward man lacks black background. 落后的男子缺少黑色背景。
- A substitution, an exchange, or an interchange. 交换代替、交换或互换
- The calcaneus projects backward behind the ankle. 跟骨突出于踝部的后方。
