a normal example: 我吃面包(I eat bread) and 我吃了面包(I ate bread) -你吃什么？(what do you eat?) -我吃面包。(I eat bread) -你昨天下午吃了什么？(what did you eat yesterday afternoon?) -我吃了面包。(I ate bread) this is the normal rule of 了 BUT you example is another kind of 了 the near future (in french, le futur proche) 我的梦想快要实现了。 here, we have to use 了 the reason is: we want to highlight "something happens very SOON" we use 实现了 to highlight my dream will become true in a MOMENT or RIGHT NOW! another example: 我快要去法国了。 I am going to france. it means I ll be in france in one or two days not in a month or a year I ll be there very soon. so if you want to express some phrases which happen very soon, you can use this kind of phrase: 快要/将要/快/...了。 我的梦想快要实现了。他将要去美国了。这个病人快死了。

I found this, you can have a look if your Chinese is good enough. http://baike.baidu.com/view/17367.htm 了： 助词 　　读音：le（ㄌㄜ˙）　 　　[1]用在动词或形容词后，表示动作或变化已经完成。（past time tense or something like that） 　　a) 用于实际已经发生的动作或者变化。例：他到了北京。 　　b) 用于预期或者假设的动作。 例：你先去，我下了班就去。 　　[2]用在句子的末尾或句子停顿的地方，表示变化或出现新的情况。 　　a)表示已经出现或者将要出现某种情况。 例：下雨了。 天快黑了。(This is the exact right answer for your confusion) 　　b)表示在某种条件下出现某种情况。 例：天一下雨，我就不出门了。 　　c)表示认识、想法、主张、行动等有变化。 例：我现在明白他的意思了。他本来不想去，后来还是去了。 　　d)表示催促或劝止。 例：走了，走了，不要再等了！ 好了，不要再说这个问题！ There are tons of meanings of 了. Actually we cannot entirely explain why we use it.

It's used as a modal particle here, indicating FUTURE certainty (so with or without it doesnt make a big difference to the meaning, better with it though). Also you find this usage in "明天又是星期六了。“ or ”要过新年了，人们很高兴。“

In this case, '了' is a dynamic particle for emphasis, because there's a phrase '快要‘。 So generally speaking, those examples from 'bear234' is correct. I think you may wanna remember ’快要.....了‘ as a pattern. The reason why I noticed you is your profile, it says: 今年二十三岁了。This is a correct sentence without any grammar mistakes, but it's kinda childish to me. Of course we do say 我今年**岁了 in oral, and there will be a tone when you say it make it sounds natural. As you are writing, people can not see you directly so they don't know what's your tone and your mood. Actually I would say this sentence is more oral one, not a best statement in writing. I would say 今年23岁 if I were you. Hope this will help. :)

I just don't think the situation is still the same. You're probably fighting for your dream and doing something to achieve your goal. When you're standing at a point, saying 我的梦想快要实现了, you are likely to have done something to improve the situation and it has become much better than before. At least you're closer to your dream. The situation is different now, not the same. It has changed. In this sense, I hope you can better understand 了. 明白 了 吗？ Just my own opinion. Hope it helps! Good luck!