Questions 11 to 14 are based on the passage you have just heard.

　　11.What is this passage talking about on the whole?

　　12.When did Harvard start a medical school?

　　]13.What foreign languages did Harvard teach in 1825?

　　14.What can be inferred from the passage?

　　Passage Two

　　You may not realize that fog is simply a cloud that touches the ground.Like any cloud it is composed of tiny droplets of water,or in rare cases,of ice crystals that form an ice fog.Ice fogs usually occur only in extremely cold climates,because water droplets are so tiny they don't become solid until the air temperature is far below freezing,generally 30 degrees below zero Celsius or lower.The droplets of fogs are nearly spherical.The transparency of fog depends mainly on the concentration of droplets.The more droplets,the denser the fog is.Since water is 800 times denser than air,investigators were puzzled for a long time as to why the water particles in fog didn't simply fall to the ground,making the fog disappear.It turns out the droplets do fall at a predictable rate,but in fog_creating conditions,they are either supported by rising air currents or continually replaced by new droplets condensing from the water vapor in the air.

　　Questions 15 to 17 are based on the passage you have just heard.

　　15.What is the main topic of the passage?

　　16.How are fog and clouds related according to the speaker?

　　17.Which of the following statements is true?

　　Passage Three

　　It was Anna's first experience of flying.She had always been afraid of heights and so was prepared to be frightened.Only the fact that she was going to meet her son who she had not seen for three years had given her the courage to make the flight.She sat in her seat,her hands gripping the arms,her seat belt already fastened.The airhostess was talking,telling everyone what to do in case of emergency showing them where their life_jackets were.The plane was crowded,every seat was full.From her window seat,getting out in a hurry would be impossible,thought Anna.In any case who would want to get out of a plane in mid_air?The engines began to shake___the noise increased till it was like a great rushing wind.She looked out to see the runaway slip past at astonishing speed.She wanted to cry out___to stop the plane before it left the ground,but she knew she was trapped in this great roaring machine,"I mustn't scream,"she told herself,and put her hands over her eyes.There was a strange feeling as if she were going up in a lift.The noise died down.Carefully she opened her eyes.Through the window she saw a great carpet of cloud above,so beautiful that she stared in wonder,hardly turning away from the window till they touched down."Well,Mother,"said John,"how did you enjoy your first flight?"

　　Questions 18 to 20 are based on the passage you have just heard.

　　18.Whom was Anna going to meet?

　　19.What did Anna do when the engines began to shake?

　　20.What did Anna see when she opened her eyes?