Passage 1
Over a hundred years ago in 1911,something strange was found in the glaciers of Antarctica.Crilffith Taylor—an Australian geologist,had discovered a blood red stream pouring out of the ice cascades (瀑布) of Talor Glacier!Popularly known as the Blood Falls,scientists had not been able to find the reason behind the blood red liquid flowing through the ice—until recently.The mystery of the Blood Falls had finally been solved.
When these falls were first discovered,scientists had believed that the red colour came from a large amount of red algae (海藻) concentrated in the water.Red algae contain a pigment (色素) which reflects red light,making the algae appear red.
This theory made sense,until it was later found that algae do not play a part in the red color of the flowing liquid at all.What really causes Talor Glacier’s waters appear blood red,is the presence of iron oxide in the liquid.The waters of the Blood Falls are rich in salt and iron content,and when this water comes in contact with the air,it turns red—just like rust!The water in these falls is often referred to as “brine” by scientists because of the high salt content in the water.
This reasoning behind the red colors of the falls was found back in 2003.However,the entire mystery had not yet been solved.How is it then,that the Blood Falls are not frozen?
Researchers at the University of Colorado and University of Alaska found that inside the glacier,there is a network of channels and reservoirs that move the water around.Salt water has a lower freezing temperature.In addition,when any substance undergoes a change in state,it gives off heat.Therefore,the brine actually warm itself up while it’s freezing!How this works,is that when the brine is flowing through the Talor Glacier,some of it does freeze.As a result of changing state from liquid to ice,the brine gives off heat.This heat is enough to keep the rest of the brine in liquid form,which is why it flows out of the glacier.
Incredible new chemistry facts found,and mystery solved!
1.According to the text,the red algae theory was once considered .
A.ridiculous B.reasonable
C.impractical D.complex
2.Why do the Blood Falls look red in colour?
A.Because there is too much salt and iron in the water.
B.Because the liquid is rich in red algae.
C.Because the flowing liquid reflects red sunlight
D.Because the air is thin and rare in Antarctica.
3.What is the main reason for the Blood Falls’ not freezing?
A.The water continued flowing constantly.
B.There is too much salt in the water.
C.The brine gives off heat while freezing
D.Temperatures aren’t high enough for flowing water.
4.What is the passage mainly about?
A.The discovery of the blood glacier.
B.The birth of the Talor Glacier.
C.The flowing red water in Antarctica.
D.The mystery of the Blood Falls.
Passage 2
Growing up in one of the poorest communities with most crimes in Los Angeles,US,being raised by a poorly-educated single mother and attending the worst-quality public school,not many people expected much of me,so I chose to expect something of myself.
On my 12th birthday,I bought a poster of Harvard University to hang in my room.Being at Harvard became my dream—I saw myself attending class in Sanders Theater,studying in Widener Library and eating in Annenberg Hall.Driven by this dream,I kept studying hard.I’d begin my day by asking myself these two questions—What do I want in my life?Are the things I am doing today going to get me closer to that life?
Asking myself the questions gave me the courage to ask over 50 Harvard students for advice on my application essays,it gave me the energy to study just one more hour on my SATs when others were asleep,and it gave me the determination to apply for just one more scholarship when already refused many times.Moreover,reminding myself of my goal each day made it easy to say no to the same choices my friends made,because they would never get me closer to my goal.I found that even being poor could not take away my power to decide what I chose to do with my life.
Every day I could feel myself getting closer and closer to my goal as my writing got better,my SAT score increased,and my scholarship offers started coming in.On March 31st,2011,an email arrived from Harvard.The first word was“Congratulations!”.Tears of joy filled my eyes.Who you are today is the result of the decisions you made yesterday,and who you will be tomorrow will be the result of the choices you make today.Who do you want to be tomorrow?
1.What does the first paragraph mainly tell us?
A.It describes the author’s early living conditions.
B.It proves that the author once lived an unhappy life.
C.It shows how many people treated the author badly.
D.It shares the author’s dream with readers.
2.What is the author’s attitude to the hardship?
A.Disappointed. B.Positive.
C.Thankful. D.Sorrowful.
3.What did the author want to tell us most?
A.A famous university,a successful life.
B.The earlier you set yourself a goal,the better.
C.What doesn’t kill you makes you stronger.
D.Your choices determine who you are.
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