By day 11 the ovum begins to attach and implant in the lining of the uterus . 到第11天卵子着床嵌入子宫内壁。
The partisans lay up by day and by night sallied out to attack convoys . 游击队白天隐蔽起来，夜晚出动袭击敌人的护航舰队。
By day and by night it seemed they need only reach out to touch the sky . 不分白天黑夜，他们似乎只要一伸手就可以碰到天空。
Somebody who is busy earning his livelihood by day can more easily follow a hobby at night . 那些白天为生计忙于奔波的人，到了晚上才有空搞一些自己爱好的事情。
By day the monotonous hours wore on in the same heavy, hashed manner as on that first dreary afternoon . 在白天，那沉闷的时刻，就和第一个凄凉的下午一样，忧郁寂寞地度过。
What at night had been perfect and ideal was by day the more on less defective real . 在夜里看起来完美无疵、合于理想的东西，到了白天，就变成了或多或少带有缺陷的现实之物了。
For day by day he felt more and more like a bubble filled with darkness, round which whirled the iridescence of his consciousness . 他日益感到自己象一个充满黑色的泡沫，四周缠绕着自身意识的彩虹。
Although it had such an insignificant beginning, the rumour had grown and increased in detail and importance day by day . 尽管谣言的起因是如此不足为凭，但东传西传便渐渐加油添醋，增加了重要的内容。
You can see stars by night , but not by day 你在夜晚可以看到星星，白天却看不到。
Day by day the disappointed lover peaked and pined 这失恋的人一天天地憔悴下去。
