ago / before 意为“以前”

1. ago 意为“从前；以前”， 常常表示从现在起若干时间以前，不可以单独作状语，必须和表示一段时间的词组连用，时态常用一般过去时。

2. before 意为“在...之前；以前”， 指过去某时间以前若干时间，也可以笼统地指过去的时间，可单独作状语，常与完成时态连用。

before long / long before

1. before long 意为“不久以后”，

2. long before 意为“很久以前”，

全部

1·The rain began before sunrise.

雨是在日出前开始下的。《柯林斯英汉双解大词典》

2·We should arrive before dark.

我们天黑以前应该能赶到。《牛津词典》

3·I often go running before work.

我常常在上班前跑步。《牛津词典》

4·You look different than before.

你看上去与从前不一样了。《牛津词典》

5·She'd never done Pilates before.

她以前从未做过普拉提。《柯林斯英汉双解大词典》

6·You must get home before curfew.

你必须在实行宵禁以前回到家中。《牛津词典》

7·He paused before answering.

他在回答前停了下来。《柯林斯英汉双解大词典》

8·They'll be back well before dark.

他们会在天黑以前回来。《柯林斯英汉双解大词典》

9·I woke up just before dawn.

我正好在拂晓前醒来。《牛津词典》

10·I can't recall meeting her before.

我想不起来以前曾经见过她。《牛津词典》

之前

1·We can't arrive before Friday at best.

我们无论如何星期五之前也到不了。《牛津词典》

2·Did she leave a message before she went?

她走之前留言了吗？《牛津词典》

3·Remind me to phone Alan before I go out.

提醒我在出去之前给艾伦打电话。《牛津词典》

4·Talk to me before you do anything drastic.

你采取任何重大行动之前要跟我谈谈。《牛津词典》

5·Many crew members were up before reveille.

许多船员在起床号响起之前就已经醒了。《柯林斯英汉双解大词典》

前

1·The rain began before sunrise.

雨是在日出前开始下的。《柯林斯英汉双解大词典》

2·Top the oil up before you set off.

出发前加满油。《牛津词典》

3·I often go running before work.

我常常在上班前跑步。《牛津词典》

4·He paused before answering.

他在回答前停了下来。《柯林斯英汉双解大词典》

5·I had cleared my desk before I left.

离开前我清理干净了办公桌。《牛津词典》

以前

1·She'd never done Pilates before.

她以前从未做过普拉提。《柯林斯英汉双解大词典》

2·They'll be back well before dark.

他们会在天黑以前回来。《柯林斯英汉双解大词典》

3·She had never ridden a horse before.

她以前从没骑过马。《牛津词典》

4·We should arrive before dark.

我们天黑以前应该能赶到。《牛津词典》

5·You might have told me that before!

你以前就该告诉我这件事！《柯林斯英汉双解大词典》

面前

1·His breath was hanging in the air before him.

他呼出的水汽悬浮在他面前的空气中。《柯林斯英汉双解大词典》

2·Robert Gates sat before them, almost penitent about the past.

罗伯特·盖茨坐在他们面前，对过去的事几乎无颜以对。《柯林斯英汉双解大词典》

3·As he came closer he saw a gigantic wall of raging flame before him.

当他走近时，他看到面前是一堵巨大的、熊熊燃烧的火墙。《柯林斯英汉双解大词典》

4·Everyone in the room knew it was the single hardest task before them.

屋子里每个人都知道这是摆在他们面前的一项最艰巨的任务。《柯林斯英汉双解大词典》

5·Paul appeared before the faculty to account for his various misdemeanours.

保罗在全体教职员面前解释了他的种种不端行为。《柯林斯英汉双解大词典》

先

1·He arrived before me.

他比我先到。《牛津词典》

2·I'll need to iron that dress before I can wear it.

我得先把那件连衣裙烫平再穿。《牛津词典》

3·I made a dash for the front door but he got there before me.

我向前门冲去，但他却已先我而到。《柯林斯英汉双解大词典》

4·I take great exception to the fact that you told my wife before you told me.

你还没告诉我就先对我妻子讲了，为此我非常生气。《牛津词典》

5·His secretary acts as a gatekeeper, reading all mail before it reaches her boss.

老板的秘书负责把关，所有邮件都由她先过目再呈送给他。《牛津词典》

以往

1·It buys less than it did before.

它的购买力不如以往。

2·Surprisingly, this year the loss of native fish to zander has been greater than before.

令人惊讶的是，今年被梭鲈吃掉的原生鱼比以往更多。

3·This tip relates to all the others that follow in this article, because they'll show you how your UNIX system helps serve that fresh-blogged content quicker and better than before.

这个技巧与本文后面的所有其他技巧相关，因为它们将向您表明UNIX系统如何有助于比以往更快更好地提供新鲜的博客内容。

4·Once the it environment more directly and accurately reflects the needs of the business and its processes, responses to changing market demands can be implemented much quicker than before.

一旦IT环境更直接和准确地反映了业务及其流程的需要，对不断变化的市场需求的响应就可以比以往更快地实现。

5·And as through the fulness of his love his heart did break, the Soul found an entrance and entered in, and was one with him even as before.

当他的心因充盈了爱意而破碎之时，灵魂寻出了一个入口，走进了他的心，他们于是如以往一般合为一体。

在之前

1·In the 1976 Summer Olympics, Nadia Comaneci scored a perfect 10, which was thought impossible before.

在1976年夏季奥运会上，娜迪娅·科马内奇得到了满分10分，这在之前被认为是不可能的。

2·When you understand a sentence I said you have to have the capacity to understand a sentence even if you've never heard it before.

当你在理解我所说的一句话时，你必须要拥有理解这句话的能力，即使你在之前从未听到过这句话。

3·This was rare before. Now it happens to more of us than ever.

这在之前是很少见到的，现在却越来越普遍。

4·They had to get ready before that.

他们必须在之前就准备好。

5·Whether you were hurt, embarrassed or both, the negative emotions you felt before should not remain fresh in your psyche.

你是否受到伤害，尴尬或两者你都受到，在之前感到的悲观情绪不应该再保留在你的心灵上。

过去

1·I don't want to upset him again like before.

我不愿意再像过去那样使他扫兴。《牛津词典》

2·Financially, I'm much better off than before.

我的经济状况比过去好多了。《牛津词典》

3·Today the life of the people is getting better than before.

今天人民的生活较过去强多了。《新英汉大辞典》

4·Once caught, you can never again be in the eyes to the good and the pure, what you were before.

一旦揭穿，在善良和纯洁的眼光看来，你就再也不可能是过去的你了。

5·Piracy is more controlled than before; although pirated DVDs of first-run films are available, the products largely come out after films have had their first runs in theaters.

盗版也比过去控制得更加严格；尽管盗版DVD在影片首轮放映时就有，但大部分还是在影院里第一轮放完后才出来。

先于

1·Those threatened by the new competition could bring omnibus bills before the Congress but could not secure their passage.

那些被新的竞争威胁的人们可以先于国会带来混合议案，但是不能保证通过。

2·And if you want the like predicate applied before the in-list predicate, your coding order must reflect that.

如果您想相似谓词先于列表谓词应用，则您的编码顺序必须相应反映。

3·Our friends, family, peers and superiors may be able to clearly recognize our inherent talents and abilities before we do.

我们的朋友、家人、同辈和上级可能能够先于我们清楚地辨别出我们内在的天赋和能力。

4·By 1958 he had teamed up with his friend Liam Clancy and Liam's brothers Paddy and Tom, who had come from Tipperary to America before him, and the gold continued to accrue.

1958年他伙同他的朋友雷姆-克兰西(他先于汤米从蒂帕雷里来到美国)以及雷姆的兄弟派蒂和汤姆一起成立了乐队，随后财源就滚滚而来。

5·Japanese routinely work long hours, as much from cultural constraints on leaving before colleagues as from volume of work.

日本人的日常工作时间很长，这和不倡导先于同事下班的文化约束以及工作量大有关。

(1)before and after前后，之前之后

(1)than before比以前

(1)as before如以前

(1)before long不久以后

(1)ever before以前；从前

(1)than ever before比以往任何时候更…