ifconj.
如果；假若；倘若
used to say that one thing can, will or might happen or be true, depending on another thing happening or being true
If you see him, give him this note.
你要是见到他，就把这个便条给他。
I'll only stay if you offer me more money.
你给我更多的钱我才会留下。
If necessary I can come at once.
如果有必要，我可以马上来。
You can stay for the weekend if you like.
你如果愿意就留在这里过周末吧。
If anyone calls, tell them I'm not at home.
要是有人打电话来，就说我不在家。
If he improved his IT skills, he'd (= he would) easily get a job.
他如果提高了自己的信息技术技能，就会容易找到工作。
You would know what was going on if you'd (= you had) listened.
你若是注意听了，就会知道发生什么事了。
They would have been here by now if they'd caught the early train.
假若他们赶上了早班火车，现在就该到这里了。
If I was in charge, I'd do things differently.
假若由我负责，我不会这样办事的。
If I were in charge…
假若由我负责…
Even if (= although) you did see someone, you can't be sure it was him.
即使你确实看见有个人，也不能保证那就是他。
当；无论何时；每次
when; whenever; every time
If metal gets hot it expands.
金属受热就膨胀。
She glares at me if I go near her desk.
我一走近她的办公桌，她就对我瞪眼。
（与will或would连用，表示客气地请求）
used with will or would to ask sb politely to do sth
If you will sit down for a few moments, I'll tell the manager you're here.
请稍坐，我这就告诉经理说您来了。
If you would care to leave your name, we'll contact you as soon as possible.
麻烦您留下姓名，我们会尽快与您联系的。
（用于ask、know、find out、wonder等之后，引出两个或以上的可能性之一）是否
used after ask , know , find out , wonder , etc. to introduce one of two or more possibilities
Do you know if he's married?
你知道他结婚了吗？
I wonder if I should wear a coat or not.
我不知道该不该穿外套。
He couldn't tell if she was laughing or crying.
他弄不清楚她是在笑还是在哭。
Listen to the tune and see if you can remember the words.
听听曲调，看你能否记起歌词。
（用于表示情感的动词或形容词之后）
used after verbs or adjectives expressing feelings
I am sorry if I disturbed you.
很抱歉，打搅您了。
I'd be grateful if you would keep it a secret.
你如果能对此保密，我将不胜感激。
Do you mind if I turn the TV off?
我关上电视可以吗？
（承认某事可能，但不很重要）即使，虽然
used to admit that sth is possible, but to say that it is not very important
If she has any weakness, it is her Italian.
如果要说她有什么缺点，那就是她的意大利语不大行。
So what if he was late. Who cares?
他就是迟到了又怎么样。谁在乎？
（置于形容词之前，引出对比）虽然，尽管
used before an adjective to introduce a contrast
He's a good driver, if a little over-confident.
他是个好司机，虽然有点过于自信。
We'll only do it once─ if at all .
我们就是干也只会干一次。
（请对方听自己的意见）
used to ask sb to listen to your opinion
If you ask me, she's too scared to do it.
依我看，她被吓得不敢做了。
If you think about it, those children must be at school by now.
想想吧，那些孩子现在一定在学校了。
If you remember, Mary was always fond of animals.
记得吧，玛丽总是喜欢动物。
（置于could、may或might之前，以提出建议或客气地打断别人的话）
used before could , may or might to suggest sth or to interrupt sb politely
If I may make a suggestion, perhaps we could begin a little earlier next week.
我来提个建议吧，或许我们下个星期可以早一点开始。
used to say sth about an event that may or may not happen
倘若我们再次见面，我希望他还记得我为他做的事。
If and when we ever meet again I hope he remembers what I did for him.
used to express an opinion about sth, or after a negative statement to suggest that the opposite is true
依我看，如果一定要说他像谁的话，他比较像他的父亲。
I'd say he was more like his father, if anything.
She's not thin─if anything she's on the plump side.
她并不瘦——其实她还有点胖呢。
used to give sb advice
我要是你，就会去另找工作了。
If I were you I'd start looking for another job.
used to say that you wish sth was true or that sth had happened
但愿我很富有。
If only I were rich.
If only I knew her name.
我要是知道她的名字就好了。
If only he'd remembered to send that letter.
要是他没忘记发那封信就好了。
If only I had gone by taxi.
我要是乘出租车去就好了。
used to say that sth that is happening is surprising
我很惊讶他们居然请我参加他们的婚礼——我跟他们似乎并不熟。
I'm surprised they've invited me to their wedding─it's not as if I know them well.
used to state the only situation in which sth can happen
学生只有得到老师的许可才能离开教室。
Only if a teacher has given permission is a student allowed to leave the room.
Only if the red light comes on is there any danger to employees.
只有红灯闪亮时才有危及职工的险情。
noun
informal不确定的情况
a situation that is not certain
If he wins─and it's a big if ─he'll be the first Englishman to win for fifty years.
假设他赢了——不过这还是个很大的疑问——他将成为五十年以来第一个获胜的英格兰人。
There are still a lot of ifs and buts before everything's settled.
在一切得以解决之前还有很多不定因素。
if
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2
CONJ-SUBORD (表示条件或假设)假如，如果，要是
You use if in conditional sentences to introduce the circumstances in which an event or situation might happen, might be happening, or might have happened.She gets very upset if I exclude her from anything...
要是有什么事情我不让她参加,她会非常难过。
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3
CONJ-SUBORD (用于间接疑问句)是否
You use if in indirect questions where the answer is either 'yes' or 'no'.He asked if I had left with you, and I said no...
他问我是否和你一块儿离开的,我说不是。
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4
CONJ-SUBORD (表示与句子主要部分的陈述稍有不同)即便，纵然，虽然
You use if to suggest that something might be slightly different from what you are stating in the main part of the sentence, for example that there might be slightly more or less of a particular quality.Sometimes, that standard is quite difficult, if not impossible, to achieve...
有时即便有可能达到那个标准，那也是非常困难。
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5
CONJ-SUBORD 如果…可以的话(通常与can，could, may 或 might 连用,在谈话中礼貌地提出自己的观点、转换话题或打断对方)
You use if, usually with 'can', 'could', 'may', or 'might', at a point in a conversation when you are politely trying to make a point, change the subject, or interrupt another speaker.If I could just make another small point about the weightlifters in the Olympics...
请允许我就有关奥运会举重运动员的问题再补充一点。
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6
CONJ-SUBORD (用于句首，表示礼貌地请求某人做某事)
You use if at or near the beginning of a clause when politely asking someone to do something.I wonder if you'd be kind enough to give us some information, please?
请问您能不能给我们提供一些信息？
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7
CONJ-SUBORD (用于引导从句中较次要的事实)即便
You use if to introduce a subordinate clause in which you admit a fact which you regard as less important than the statement in the main clause.If there was any disappointment it was probably temporary...
即便有点儿失望,也肯定是暂时的。
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8
PHR-CONJ-SUBORD 要是不;即使不
You use if not in front of a word or phrase to indicate that your statement does not apply to that word or phrase, but to something closely related to it that you also mention.A number of recent advances hold out if not the hope of a cure, then at least the possibility of some drug which could stop the spread of the virus...
近来的一些进展即使不能提供治愈的希望,也至少有望研制出来某种药物来阻止病毒的传播。
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9
PHR-CONJ-SUBORD (用于过去时,加强语气)如果真的…
You use if ever with past tenses when you are introducing a description of a person or thing, to emphasize how appropriate it is.I became a distraught, worried mother, a useless role if ever there was one...
我变成了一个忧心如焚的母亲,一个全无用处的角色。
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10
PHR-CONJ-SUBORD (与过去时连用，引出一个相对合理的理由)即使仅仅为了(或因为)…
You use if only with past tenses to introduce what you think is a fairly good reason for doing something, although you realize it may not be a very good one.She writes me often, if only to scold me because I haven't written to her...
她常来信,即使仅仅为了责怪我还没回信给她。
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11
PHR-CONJ-SUBORD 要是…多好
You use if only to express a wish or desire, especially one that cannot be fulfilled.If only you had told me that some time ago...
要是你早些时候告诉我该多好啊！
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12
PHR-CONJ-SUBORD (表示判断)好像,仿佛,似乎
You use as if when you are making a judgment about something that you see or notice. Your belief or impression might be correct, or it might be wrong.The whole room looks as if it has been lovingly put together over the years...
整个房间看起来好像是经过了多年的精心布置。
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PHR-CONJ-SUBORD (表示类比)好像，仿佛，似乎
You use as if to describe something or someone by comparing them with another thing or person.He points two fingers at his head, as if he were holding a gun...
他把两根手指指向他的头,仿佛他正举着一支枪。
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14
PHR-CONJ-SUBORD (强调某物不是真的)好像…一样,仿佛,似乎
You use as if to emphasize that something is not true.My husband, for some unknown reason, suggested that I loved my birds more than him: as if I would...
我丈夫,莫名其妙地,暗示我爱鸟甚于爱他：仿佛我真如此似的。
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15
PHRASE 要说真有什么的话;甚至正相反
You use 'if anything' to introduce something which strengthens or changes the meaning of the statement you have just made, but only in a small or unimportant way.Living together didn't harm our friendship. If anything it strengthened it...
在一起住并没有损害我们的友谊。要说真有什么的话,它反而巩固了我们的友谊。
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16
PHRASE 显然不是
You use 'It's not as if' to introduce a statement which, if it were true, might explain something puzzling, although in fact it is not true.I am surprised by the fuss she's making. It's not as if my personality has changed.
她的大惊小怪令我很吃惊。显然不是我的个性改变了。
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PHRASE (用于给人建议)如果我是你的话
You say 'if I were you' to someone when you are giving them advice.If I were you, Mrs Gretchen, I just wouldn't worry about it...
要是我是你,格蕾琴夫人,我一点都不会担心。
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I could do it now , if you like .
如果你愿意的话，我现在就可以做这事。
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You can come with us if you want to .
如果你愿意可以跟我们一起来。
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Put your hand up if you need more paper .
若有人还要纸，请举手。
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If that is the case , we need more staff .
如果真是那样，我们就需要更多的员工了。
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If that is the case , we need more staff .
如果真是那样，那我们就需要更多的员工了。
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Let me know if you have any problems .
你若有困难就告诉我。
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If that 's what you think , you 're way off base .
你如果那么想就全错了。
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I went to see if my old school was still there .
我去看过母校是否依然存在。
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If you should change your mind , do let me know .
假如你改变主意的话，一定要告诉我。
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What difference will it make if he knows or not ?
他知不知道有什么关系吗？
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I can 't work if I 'm cold .
我要是觉得冷就干不了活。
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If you have any issues , please call this number .
如有问题，请拨打这个电话号码。
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She asked me if I would give her English lessons .
她问我愿不愿意给她上英语课。
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Perhaps it would be better if you came back tomorrow .
如果你明天回来，也许更好。
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That was a disaster if ever there was one !
那确实是场灾难！
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I 'll get there , even if I have to walk .
我就是走也要走到那儿去。
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If we take the lead in this , others may follow .
如果我们在这方面带头行动，其余的人就会跟着来。
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Put your hand up if you know the answer .
知道答案就举手。
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If he can 't help , there 's always John .
如果他帮不上忙，总还有约翰呢。
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If you love each other , why not get married ?
要是你们彼此相爱，干吗不结婚呢？
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You really need to be mobile if you live in the country .
如果你住在乡村，你确实要有一辆汽车。
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If necessary , you can contact me at home .
必要的话，我在家时你也可以和我联系。
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If you want another drink , just help yourself .
你要是想再喝一杯就请自便。
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If only I could have helped put matters right .
要是我当时能帮着把错误纠正过来就好了。
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If they entered the building they would be breaking the law .
如果进入那栋大楼，他们就会触犯法律。
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Feel free to ask questions if you don 't understand .
你要是不懂，可以随便提问。
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If he wants to see me , he should make the first move .
他要是想见我，就得采取主动。
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If I had the choice , I would stop working tomorrow .
如果让我选择，我明天就停止工作。
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He 'll do the job if you make it worth his while .
你要是给他的报酬丰厚，他会做这份工作的。
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If necessary I can come at once .
如果有必要，我可以马上来。
- 习语