,　　　　　　　　　　　　　[学生用书单独成册])

　　课时作业3　(A卷)

　　Ⅰ.品句填词

　　1．He spoke so loudly as to make himself ____________(understand)．

　　2．The boy ____________(be) late, his teacher was very angry.

　　3．In addition ____________ these books，there are many desks in the room.

　　4．The bus stops regularly to set down and pick ____________ passengers.

　　5．The enemy troops were fleeing ____________ all directions.

　　6．Can you make sense ____________ what this writer is saying?

　　7．I am bound to say I disagree ____________ you on this point.

　　8．He is recognised ____________ a movie star in Hong Kong.

　　9．The doctors hold out little hope of his ____________(recover)．

　　10．Man was responsible for the ____________(survive) of his family.

　　答案：1.understood　2.being　3.to　4.up　5.in　6.of　7.with　8.as　9.recovery　10.survival

　　Ⅱ.阅读理解

　　Far from the land of Antarctica，a huge shelf of ice meets the ocean.At the underside of the shelf there lives a small fish，the Antarctic cod.

　　For forty years scientists have been curious about that fish.How does it live where most fish would freeze to death？It must have some secret.The Antarctic is not a comfortable place to work and research has been slowed.Now it seems we have an answer.

　　Research was begun by cutting holes in the ice and catching the fish.Scientists studied the fish's blood and measured its freezing point.

　　The fish were taken from seawater that had a temperature of －1.88 ℃ and many tiny pieces of ice floating in it.The blood of the fish did not begin to freeze until its temperature was lowered to －2.05 ℃.That small difference is enough for the fish to live at the freezing temperature of the ice­salt mixture.

　　The scientists'next research job was clear：Find out what in the fish's blood kept it from freezing.Their search led to some really strange things made up of a protein(蛋白质)never before seen in the blood of a fish.When it was removed，the blood froze at seawater temperature.When it was put back，the blood again had its anti­freeze quality and a lowered freezing point.

　　Study showed that it is an unusual kind of protein.It has many small sugar molecules(分子)held in special positions within each big protein molecule.Because of its sugar content，it is called a glycoprotein．So it has come to be called the anti­freeze fish glycoprotein or AFGP.

【解题导语】　本文主要介绍了一种生活在南极海水中的鱼。