by accident/by chance
The other day Imet her by accident.
前几天我偶然遇到了她。
accident 事故 incident 事件
without accident
The night passedwithoutaccident.
一夜无事。
on account of
The flight waspostponed on account of bad weather.
因为天气恶劣，飞行延期了。
of no account 无论怎样也不
in the air 悬而未决，流传开来
He toldreporters today that the president's trip to Moscow is up in the air.
今天他告诉记者们总统是否前往莫斯科尚未确定。
on the air
She is going on the air as presenter ofa new show
她即将上电视主持一档新节目。
on tv 上电视
case n.情况
casual a.偶然的
in any case 无论如何
In any case, I must find anapartment this time.
无论如何，这次我一定要找到一间租房了。
in no case 无论如何都不
In no case should you leaveyour parents.
无论如何都不应该离开你的父母父母。
in case of 如果
In case of difficulty, justcall on me.
如有困难，找我好了。
in case 以防 万一
Please keep aneye on the stove in case the milk boils.
劳神照料炉上的牛奶，别沸溅了。
They are afraidto contact the social services in case they arelabelled a problem family
由于害怕被贴上“问题家庭”的标签，他们不敢联系社会福利机构。
短语送几个：
on the basis of 根据
out of breath 喘不过气来
in conclusion 总之
in addition 另外
in addition to 在…之外
on average 平均
on board 在船（飞机、车）上
in common 共有 共用
on business 因公，因公事
以上是小编为大家整理的内容，距离考试为剩不多，坚持的人最幸运。希望大家能够不后悔奋战这么久，备考不易，迈进考场时，希望你是信心丰沛的那个。文都考研也会陪伴大家一起将考研英语复习到底。
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