它使用定量数据和数学模型作为分析工具，研究这些物体在过去、现在和未来的数量。
It studies these populations, in the past, present and future, using quantitative data and mathematical models as tools of analysis.
它使用定量数据和数学模型作为分析工具，研究这些人口在过去、现在和未来的情况。
It studies these populations in the past, present and future using quantitative data and mathematical models as tools of analysis.
而当出现了封闭的时间型曲线时，一些事件既出现在过去，也正在未来出现。
But in the presence of closed timelike curves, some events are in our past and also in our future.
我们需要知道在过去、现在发生的事情，来了解如何去创造我们的未来。
We need to know what happened in the past, and what's happening now, to understand how to create our version of the future.
我们现在所看到的，也才是一个开端而已，肉品消耗量在过去五十年已增加五倍，而未来五十年恐怕会再加倍。
What we're seeing is just the beginning, too. Meat consumption has increased five-fold in the past fifty years, and is expected to double again in the next fifty.
业务时间涉及到跟踪某些业务条件在过去、现在或未来的哪个时刻有效。
Business time involves tracking when certain business conditions are, were, or will be valid.
没有人生活在过去，也没有人生活在未来，现在是生命确实占有的唯一形态。——叔本华。
No one lives in the past, no one lives in the future, and now is the only form of life is indeed a possession. - Schopenhauer.
如果我们在过去和现在之间争吵不休，我们将会发现我们已经失去未来。
If we open a quarrel between the past and the present, we shall find we have lost the future.
不要因为生活在过去的回忆或未来的幻想中，而让你现在的时间从指缝溜走。应当活在当下，生活在生命中的每一天。
Don? T let your life slip through your fingers by living in the past or for the future. By living your life one day at a time, you live all the days of your life.
没有人生活在过去，也没有人生活在未来，现在是生命确实占有的唯一形态。
No one living in the past, and no one lives in the future, it is the only form of life indeed occupies.
如果现在我们不能活在未来，明天你就会被淘汰。(将来必会活在过去之中)。
If you don't live, in the future today, you will live in the past tomorrow.
一条腿站在过去，一条腿站在未来……那我们正在朝现在撒尿就没什么可惊讶的了。
DJ: With one leg in the past and one in the future… it's no wonder we're pissing on the present.
我们如果在过去和现在中争吵，我们会发现我们已丢失了未来。
If we can open a quarrel between the past and the present, we shall find that we have lost the future.
这点我相当确定：如果我们争论在过去和现在，我们将会失去未来。
Of this I am quite sure, that if we open a quarrel between the past and the present, we shall find we have lost the future.
那些还在时间上徘徊的人，那些还停留在过去，想象未来的人，那些白白虚度光阴的人，不要再犹豫，只有把握现在，才是最理想的唯一选择。
Those who are hanging around in time, those who still remain in the past, imagine the future, those who live artificially, who in vain, do not hesitate, only to grasp now, the only option is the best.
不要沉迷在过去或未来中而让现在从指缝间匆匆溜走。
Don't let your life slip your fingers by living in the past or for the future.
不要为了过去呜咽，它已过去了；不要为了未来而感到压力，由于它还没来；活在当下，把现在过得美丽。
Don't cry over the past, it's gone. Don't stress about the future, it hasn't arrived. Live in the present and make it beautiful.
大多数人是囚犯，因为他们总是想着未来或活在过去，他们的心不在现在，可是现在是一切事情开始的地方。
Most people are prisoners, thinking only about the future or living in the past. They are not in the present, and the present is where everything begins.
大多数人是囚犯，因为他们总是想着未来或活在过去，他们的心不在现在，可是现在是一切事情开始的地方。
Most people are prisoners, thinking only about the future or living in the past. They are not in the present, and the present is where everything begins.
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