whether / if

1. whether 意为“是否”， 在引导名词性从句时，应注意如下几点不能用if：1) 和or not连用；2) 在从句中作介词宾语；3)主语从句位于句首；4) 引导不定式短语；5) 引导表语从句；6)在有些动词后，如discuss

2. if 意为“是否；如果”， 在引导条件状语从句时，用if不用whether

全部

1·Check whether a fuse has blown.

检查一下保险丝是否烧断了。《牛津词典》

2·West had to decide whether to play a heart.

韦斯特不得不决定是否要出一张红桃牌。《柯林斯英汉双解大词典》

3·I asked whether they could change my ticket.

我问他们是否可以给我换票。《牛津词典》

4·Whether I believe you or not is irrelevant now.

我是否相信你，现在已无关紧要了。《牛津词典》

5·It remains to be seen whether his project will fly.

他的计划能否成功尚需拭目以待。《牛津词典》

6·All she's worried about is whether he is all right.

她所担心的只有他是否都好。《柯林斯英汉双解大词典》

7·Your lawyer can advise you whether to take any action.

你的律师可以告诉你是否起诉。《牛津词典》

8·I hear you're taking bets on whether she'll marry him.

我听说你愿意拿她是否会嫁给他的事和人打赌。《牛津词典》

9·They deliberated on whether to continue with the talks.

他们仔细考虑了是否继续谈判的问题。《牛津词典》

10·We're debating whether or not to go skiing this winter.

我们盘算着今年冬天是否去滑雪。《牛津词典》

是否

1·Check whether a fuse has blown.

检查一下保险丝是否烧断了。《牛津词典》

2·West had to decide whether to play a heart.

韦斯特不得不决定是否要出一张红桃牌。《柯林斯英汉双解大词典》

3·I asked whether they could change my ticket.

我问他们是否可以给我换票。《牛津词典》

4·All she's worried about is whether he is all right.

她所担心的只有他是否都好。《柯林斯英汉双解大词典》

5·Your lawyer can advise you whether to take any action.

你的律师可以告诉你是否起诉。《牛津词典》

无论

1·This happens whether the children are in two-parent or one-parent families.

这种情况无论在双亲家庭还是单亲家庭的孩子身上都会发生。《柯林斯英汉双解大词典》

2·You are entitled to a free gift whether you accept our offer of insurance or not.

无论你接不接受我们的保险提议，你都可以免费得到一份礼物。《牛津词典》

3·There seems to be little difference whether you eat all your calorie allowance at once, or spread it over the day.

无论你是一次性吃完全天的卡路里限量还是分散在一天里吃，似乎没多大区别。《柯林斯英汉双解大词典》

4·The substance does not dissolve in water whether heated or not.

无论加热与否，这种物质都不溶于水。

5·A man, remember, whether rich or poor, should do something in this world.

要记住，一个人，无论贫富，都应该在这个世界上有所作为。

是不是

1·Privately, she worries about whether she's really good enough.

私下里，她担心她是不是真的够好。《柯林斯英汉双解大词典》

2·I discussed with my intimate friends whether I would immediately have a baby.

我和我的密友们商量我是不是该马上要孩子。《柯林斯英汉双解大词典》

3·The foreman was asked by the clerk whether the jurors had reached verdicts on which they all agreed.

书记员问陪审团主席是不是陪审员们已作出了全体一致的裁决。《柯林斯英汉双解大词典》

4·Have you seen whether they took Heidi away?

你有没有看到他们是不是把海蒂带走了？

5·I don't know whether I should tell Eric my thoughts or not.

我不知道是不是该和艾瑞克谈谈我的想法。

不论

1·All substances, whether they are gaseous, liquid or solid, are made of atoms.

一切物质，不论它们是气体、液体还是固体，都是由原子构成的。《新英汉大辞典》

2·If they are around the table, invite them and, jointly determine the best way forward, whether your connection with them is formal or informal.

如果他们在桌子周围，邀请他们，共同决定前进的最佳方式，不论您跟他们的联系是正式还是非正式的。

3·If they should be around the table, invite them and, jointly, determine the best way forward, whether your connection with them is formal or informal.

如果他们应该在场，要邀请他们加入，一起决定前进的最佳方式，不论您跟他们的联系是正式还是非正式的。

4·When we take a risk we cannot know beforehand what will happen, but if we try our best we are certain to gain something positive from the experience whether we win or lose.

当我们冒险时，我们无法预知会发生什么事，但如果我们尽力而为，不论结果是输是赢，我们必定可以从这次的经验中获得一些积极的启示。

5·It really depends on the scope and kind of changes you are making whether you should accept right away or not.

这真的依赖于您正在进行的变更的范围和类型，不论您应该马上接受与否。

(1)whether or是…还是…