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- preconditions are often needed 先决条件往往是必要的。
- Enumerating sentences of CFL are often needed when testing programs involving complex data structures. 在测试基于复杂数据结构的程序时,需要用到上下文无关语言句子的枚举。
- The xenogenic bone seemed to induce rejection in vivo, In the sevious cases immunosuppressive treatment was often needed. 认为，异种骨在人体内存在排异反应，严重者需用免疫抑制剂治疗。
- The vehicle should be furnished with components and materials which are often needed in maintenance of guestrooms and publice area. 房间维护车上通常应备用维护客房和公共区域通常所需用到的零备件和材料。
- It is quite difficult to do with any sort of accuracy, because the wind speeds and directions are very changeable, so empirical models and methods are often needed. 要具有一定的精确度十分困难，因为风速和风向都太容易变化了，所以常常需要用到经验模型方法。
- Animals are often personified in fairy tales. 动物常在童话中被拟人化。
- True visionaries are often misunderstood by their own generation. 真正有远见卓识的人往往招致同时代人的误解。
- Histories are often warped by biases. 历史常为偏见所曲解。
- Earth worms are often used as bait. 蚯蚓常用作鱼饵。
- New workers often need close supervision. 新工人通常需要严密的管理。
- Young plants are often killed by frost. 植物的幼苗常因严寒而冻死。
- Romantic heroines are often capricious. 浪漫的女主人公往往难以捉摸。
- Women are often oppressed by men. 女人经常受男人压迫。
- Anthems are often with words taken from the Bible. 圣歌的歌词多取自于《圣经》。
- Teachers are often compared to burning candles. 人们总是把老师比喻为燃烧的蜡烛。
- Rooms in cheap hotels are often dingy. 在低级旅馆中全是又黑又脏的房间。
- American girls are often very pretty. 美国女孩多很漂亮。
- Own brand goods are often cheaper. 有本店商标的货物往往比较便宜。
- Women are often said to be more emotional than men. 人们常说女人比男人更富于感情。
- Cranberries are often used for making sauce. 酸果蔓常被用来做成调味酱。
