if
conjunction uk/ɪf/ us/ɪf/
(IN THAT SITUATION)
A2 假如，如果
used to say that a particular thing can or will happen only after something else happens or becomes true
I'll pay you double if you get the work finished by Friday. 如果你周五前完工，我付你双倍的报酬。
We'll have the party in the garden if the weather's good. If not (= if the weather is not good), it'll have to be inside. 如果天气好的话，我们将在花园里开派对。如果不好，就只好在室内了。
If anyone calls, just say I'll be back in the office at four o'clock. 要是有人给我打电话，请告诉他们我4点钟回办公室。
If she hadn't called, I wouldn't have known. 要不是她打来电话，我还不知道呢。
I wouldn't work for them (even) if they paid me twice my current salary. 即使他们付给我的工资是现在的两倍，我也不会为他们干活。
We'll deal with that problem if and when it arises. 等到那个问题出现我们再处理。
If disturbed, the bird may abandon the nest, leaving the chicks to die. 如果受到惊扰，鸟可能会弃巢而去，留下雏鸟，任由它们死亡。
虽然，即使
although
They're great kids, even if they can be demanding. 虽然他们要求多多，但他们是很好的孩子。
literary It was a hot, if windy day. 那天虽然有风，却依然很热。
B1 当，每当
every time
If water is heated to 100°C it turns to steam. 水被加热到100摄氏度时，就会变成蒸汽。
If I don't get enough sleep I get a headache. 我睡眠不足时就会头疼。
如果…是真的
used to mean "if it is true that"
I'm very sorry if I've offended you. 如果我冒犯了你的话，我很抱歉。
- More examples
- You'll feel cold if you don't wear a coat.
- You have to go to college for a lot of years if you want to be a doctor.
- Try to act confidently, even if you feel nervous.
- The TV won't work if the aerial's not connected.
- Biscuits will stay crisp if you keep them in an airtight container.
(WHETHER)
B1 （用于引出从句，常为间接引语）是否
used to introduce a clause, often in indirect speech, that shows two or more possibilities
Mrs Kramer called half an hour ago to ask if her cake was ready. 克雷默夫人半小时前来电话问她的蛋糕做好了没有。
I don't care if he likes it or not - I'm coming! 我不在乎他乐不乐意，我反正要来！
I was wondering if you'd like to come to the cinema with me this evening? 不知你今晚想不想与我一起去看电影？
Compare: whether
- More examples
- I must see if my flatmate has paid those bills yet.
- We asked if the computer could access the internet.
- You could always call Susie and see if she might babysit.
- I asked if she'd like to come out with us tonight.
- I couldn't find the station, so I asked someone if they could direct me.
(REQUEST)
（用于礼貌地作出请求或评论）
used when you want to make a polite request or remark
If you'd like to take a seat, Mr Chang will be with you in a moment. 您请先坐一会儿吧，张先生一会儿就过来。
Would you mind if I open/opened (= can I open) the window? 我开窗您介意吗？
There are, if you don't mind me saying so, one or two problems with this plan. 恕我冒昧，我觉得这个计划有一两处问题。
Idioms
if and whenidiom mainly US (UK usually as and when) 当…时，到…的时候
at the time that something happens
We don't own a car - we just rent one if and when we need it. 我们没有车——只是在需要的时候就去租一辆。
if I were youidiom B1 如果我是你的话
used when you give someone advice
If I were you, I'd probably go. 如果我是你，我可能会去。
I think I'd take the money if I were you. 如果我是你，我想我会接受这笔钱。
if need beidiom 如果有必要的话
if it is necessary
If need be, we can take two cars. 如果有必要的话，我们可以要两辆车。
if you willidiom (also if you like) 如果你愿意那样说的话
used to say that a particular expression is one way of saying something, especially to suggest that some people may not choose to say it that way
I did very well in school , with a "genius IQ" if you will. 我在学校成绩很好，有“天才智商”，如果你愿意那样说的话。
if
noun [ C usually singular ] informal uk/ɪf/ us/ɪf/
不确定因素;未决之事;疑问
something that is not certain or not yet decided
There's a big if hanging over the project (= it is uncertain whether the project will happen). 这个计划能否启动仍然悬而未决。
Idiom
no ifs or butsidiom UK (US no ifs, ands, or buts) （对儿童用语）少跟我胡搅蛮缠，别找借口
something that you say to a child to stop them arguing with you when you want them to do something
I want no ifs or buts - just get on and tidy your room now. 少给我胡搅蛮缠——现在就赶快打扫你的房间。