1,There are many mysteries in nature.自然界有許多神秘的東西
2,Mysteries are things we don't understand, such as how the Egyptian pyramids were built.神秘是我們無法理解的事情丸卷，比如埃及金字塔是如何建造的。
3,In fact, we are surrounded by mysteries.事實(shí)上谜嫉，我們被神秘包圍著
4,What we know about the world seems like very little.我們對(duì)這個(gè)世界的了解似乎很少
5,Scientists tell us that what we see in the universe is only a small part of what is there.科學(xué)家告訴我們，我們?cè)谟钪嬷锌吹降闹皇怯钪嬷械囊恍〔糠?/p>
6,The rest is invisible哆档，including dark matter and dark energy.其余的是看不見的住闯，包括暗物質(zhì)和暗能量。
7,These two unknowns make up around 95% of the universe.這兩個(gè)未知數(shù)約占宇宙的95%寞秃。
8,Evidence for their existence comes from their effects on what we can observe, such as the motion and positions of distant galaxies.它們存在的證據(jù)來自它們對(duì)我們所能觀察到的東西的影響偶惠，例如遙遠(yuǎn)星系的運(yùn)動(dòng)和位置。
9忽孽、Yet, though we know very little, we are able to build airplanes and communicate with smartphones.然而谢床，盡管我們知之甚少厘线，但我們能夠建造飛機(jī)和智能手機(jī)通信。
10,In some ways we humans are very smart, or at least we think we are.在某些方面渡讼，我們?nèi)祟惙浅Ｂ斆鞫担蛘咧辽傥覀冋J(rèn)為我們很聰明成箫。
11,We still need to face big issues, like climate change, and that is going to be a huge challenge.我們?nèi)匀恍枰鎸?duì)像氣候變化這樣的大問題旨枯，這將是一個(gè)巨大的挑戰(zhàn)
12,The challenge for humans will be our ability to adapt to our changing environment.人類面臨的挑戰(zhàn)將是我們適應(yīng)不斷變化的環(huán)境的能力。
13皂贩，What about other forms of life?那么其他形式的生命呢?
15,How do they adapt?它們是如何適應(yīng)的昆汹？
14,Seasonal variations, for example, can be one of the greatest challenges for animals to overcome.例如，季節(jié)性變化可能是動(dòng)物克服的最大挑戰(zhàn)之一满粗。
15.h challenges is a great achievement, but hardly easy.克服這些挑戰(zhàn)是一項(xiàng)偉大的成就，但并非易事本冲。
16,Some birds migrate thousands of kilometers each year to deal with seasonal changes.一些鳥類每年遷徙數(shù)千公里以應(yīng)對(duì)季節(jié)變化劫扒。
17,These migrations are amazing.這些遷徙是驚人的
18,Birds don't carry maps or compasses, yet they know where to go.鳥類不帶地圖或指南針檬洞，但它們知道去哪里沟饥。
19,They have developed the ability to see the Earth's magnetic field.他們已經(jīng)發(fā)展了觀測(cè)地球磁場(chǎng)的能力
20,This ability is a wonder of nature.這種能力是大自然的奇跡
21,It takes advantage of the fact that the earth is like a huge bar magnet.它利用了這樣一個(gè)事實(shí)：地球就像一個(gè)巨大的磁棒
22,It has a north pole, which is positive, and a south pole, which is negative.它有一個(gè)北極，它是正的广料，還有一個(gè)南極幼驶，它是負(fù)的。
23,Somehow the birds are able to see this magnetic field and use it to their advantage.不知怎的盅藻，這些鳥能夠看到磁場(chǎng)畅铭，并利用它來獲取它們的優(yōu)勢(shì)勃蜘。
24,And even the way birds fly together is amazing.甚至連鳥兒一起飛翔的方式都令人驚嘆。
25,Many migrating birds fly in a V formation.許多候鳥以V字形飛行缭贡。
26,They do this to conserve energy.他們這樣做是為了保存體力。
27,In a V formation, birds can use the energy of the birds in front of them.在V形隊(duì)形中坑资，鳥類可以利用前方鳥類的能量穆端。
28,This energy comes from the air currents generated by the wings.這種能量來自于由翅膀產(chǎn)生的氣流。
29,Conserving energy is necessary for the birds to survive the long journey.節(jié)約能源對(duì)鳥類在長途旅行中生存是必要的
30,How do the birds know this?鳥是怎么知道的体啰？
31,It's truly amazing how the birds know this.鳥類是如何知道這一點(diǎn)的真的很神奇。
