Have you ever been in such cold weather that you could see your breath? Did you feel as thoughyou were a mythicalcreature emitting a cloud of mist each time you breathed out? Well, sorry to ruin your fantasy, but there’s a scientific explanation for this fascinating phenomenon.
As you probably already know, every time you inhale, your lungs absorb oxygen from the air. When you exhale, your lungs put carbon dioxide(CO2) back into the air. The warm air released from your body with each exhalationcontains vapor because of the moisture from your lungs, throat, and mouth. The warmth gives the particles of water the energy they need to keep moving rapidly. But when the air outside is cold, the water particles slow down and move closer together, forming little drops of water in the air, which is a process referred to ascondensation. These drops of water suspended in the air appear like a cloud under lights, which is why you are able to see them.
How cold does it need to be for you to witness this phenomenon? Actually, there’s no set answer. It depends on other factors, such as the humidity level of the air—the morehumid the air, the morevisible your breath will be. But generally speaking, you can usually see your breath when the temperature reaches around 7°C or cooler. One tip to see it more easily is to open your mouth wide and exhale from deeper in your throat so that the air coming out will be warmer and carry more vapor.
So, the next time the mercuryin the thermometerplummets, step outside, take a deep breath, exhale, and enjoy the spectacle!
1. Which of the following words in the passage means “the transformation of a gas into a liquid”?
(A) Spectacle.
(B) Exhalation.
(C) Phenomenon.
(D) Condensation.
2. Which of the following statements is true about the air exhaled from the human body?
(A) It stops moving if the temperature is too low.
(B) It contains a large amount of oxygen.
(C) It is a gas and normally not visible.
(D) It is completely dry and warm.
3. According to the passage, under which circumstances will you be less likely to see your breath?
(A) Breathing out air on a freezing rainy day.
(B) Releasing your breath when the weather is chilly.
(C) Blowing out your breath when the temperature is below 0°C.
(D) Taking a deep breath under the sunlight and expellingit from the nose.
答案：1.D 2.C 3.D
單字片語整理
Words in Use
●
emit
[ɪˋmɪt]
vt. 排放；散發
I could feel heat emitted from the fireplace.
我可以感受到壁爐散發出來的熱。
多益金色
英檢中高
●
absorb
[əbˋsɔrb]
vt. 吸收；理解
Sponges are used to absorb liquids.
海綿可用來吸收液體。
I couldn’t absorb everything I read.
所有讀過的東西我並非都能理解。
I was so absorbed in my work that I didn’t hear you calling me.
我太投入工作，因此沒聽到你在叫我。
I was so buried in my work that I didn’t hear you calling me.
我太投入工作，因此沒聽到你在叫我。
多益藍色
英檢中級
高中 Level 4
●
vapor
[ˋvepɚ]
n. . 蒸氣
The doctor used water vaporto treat my sore throat.
醫生用水蒸氣來治療我的喉嚨痛。
英檢中級
高中 Level 6
●
particle
[ˋpɑrtɪk!]
n. 微粒；粒子
The surface of the desk was covered with particles of dust.
書桌的表面布滿了灰塵微粒。
Electrons and protons are atomic particles.
電子和質子都是原子粒子。
高中 Level 5
●
suspend
[səˋspɛnd]
vt. 中斷，中止；吊銷（執照）；垂掛，懸掛
=
stop
=
hang
=
interrupt
The meeting was suspended because of the blackout.
因為停電，會議被中斷了。
Toby was suspended from school because he got caught cheating on a test.
托比因為考試作弊被抓到，所以被停學了。
Peter’s license was suspended for drunk driving.
彼得因為酒駕，駕照被吊銷了。
As part of the exhibition, the museum suspended
dozens of large paintings by wires from the ceiling.
作為展覽的一部分，博物館從天花板上用金屬線懸掛數十幅大型畫作。
多益藍色
英檢中級
高中 Level 5
●
witness
[ˋwɪtnɪs]
n. 證人
vt. 目擊
Vince is the only witness to the murder.
文斯是凶殺案唯一的證人。
Will’s success bears witness to his hard work over the past 10 years.
威爾的成功為他 10 年來的努力作了見證。
Did you witness the car accident yourself?
你親眼目睹了這場車禍嗎？
多益藍色
英檢中級
高中 Level 4
●
humidity
[hjuˋmɪdətɪ]
n. 溼氣，溼度
=
moisture
I hate summer because of the humidity.
我討厭夏天，因為溼氣太重。
高中 Level 4
●
thermometer
[θɚˋmɑmətɚ]
n. . 溫度計
According to the thermometer on the wall, the
temperatureis now 36 degrees Celsius.
根據牆上的溫度計顯示，目前氣溫為攝氏 36 度。
多益藍色
英檢中高
高中 Level 6
●
spectacle
[ˋspɛktək!]
n. . 奇觀
Niagara Falls is a real spectacle.
尼加拉瀑布真是個奇景。
Wayne made a spectacleof himself after he got
drunk at a dinner party.
韋恩在晚宴上喝醉，出了洋相。
英檢中高
高中 Level 6
●
transformation
[͵trænsfɚˋmeʃən]
n. 變形，轉型
The country ’s political status has experienced a dramatic transformation in recent years.
這些年來，該國政局經歷了戲劇化的轉變。
Today's topic is India's transformation from poverty to prosperity.
今天的主題是印度從貧窮轉型到富裕的過程。
高中 Level 5
●
mythical
[ˋmɪθɪkəl]
a. 神話的；虛構的
●
plummet
[ˋplʌmɪt]
vi. 驟降，暴跌
After the two countries declared war on each
other, their stock markets plummeted.
那兩國彼此宣戰後，他們的股市便暴跌。
●
exhalation
[͵ɛksəˋleʃən]
n. 呼出
●
condensation
[͵kɑndɛnˋseʃən]
n. 凝結
●
mercury
[ˋmɝkjərɪ]
n. 水銀
英檢中高
●
expel
[ɪkˋspɛl]
vt. （從體內或容器內）排出；使退學
Those guilty of academic misconduct may be expelled.
犯了學術舞弊的人可能被退學。
英檢中高
Practical Phrases
●
carbon dioxide
二氧化碳
Plants absorb carbon dioxide and produce oxygen.
植物吸收二氧化碳並且製造氧氣。
●
be referred to as...
被稱作⋯⋯
The president of the US is sometimes referred to as the chief executive.
美國總統有時被稱作最高行政首長。
●
generally speaking
一般而言
= in general
●
take a deep breath
深呼吸
I always take a deep breath before going on the stage.
我每次上臺前都會深呼吸。
●
as though + S + V
好像／彷彿⋯⋯
Tina acts as though she's tough. In fact, she is quite timid.
蒂娜表現得好像她很強悍。其實，她膽小如鼠。
