完形填空

　　I will never forget the two impressive things that happened last winter．One of my classmates and I were 　　1　　 our project work late at night on my university's campus far from home．Since there was 　　2　　 in the forecast, I had worn a winter 　　3　　 to school that day with a raincoat in my bag．

　　Throughout our work on the project, I could 　　4　　 that my friend was tired from a very long day working．As we stepped outside to begin the 　　5　　 walk home, I 　　6　　 she was shivering(颤抖)．The temperature had dropped to the low thirties(Fahrenheit)and she 　　7　　 had a sweater on．I 　　8　　 offered her my warm jacket．She accepted it and asked me what I 　　9　　 wear then．I told her I had another one and pretended that my 　　10　　 was a jacket．She said later that she 　　11　　 the next morning and the first thing on her mind was feeling moved about my 　　12　　 of the jacket．

　　Coincidentally(碰巧), the next day I went to an open-air play and I was freezing 　　13　　 I didn’t expect it to be so 　　14　　．A person who I hardly 　　15　　 insisted that I wear his jacket．I was 　　16　　 touched by this warm gesture．He was so matter-of-fact(讲究实际的)about me 　　17　　 his coat, too：he simply took it off and handed it to me telling me that I should 　　18　　 it．I used to think that this vast universe was a cold 　　19　　．It turns out that even when the temperature drops low, the people never 　　20　　 to warm each other's hearts．

完形填空

　　As scientists learn more about the causes of earthquakes, they become better able to predict them．First of all, they know that quakes are 　　1　　 to occur in areas where the tectonic(地壳构造的)plates push 　　2　　 each other．They 　　3　　 these areas closely, using different instruments．They 　　4　　 the vibrations(震动)of the earth with seismographs(地震仪), which 　　5　　 on rolls of paper all movements, both large and small．Scientists usually use the Richter scale(里氏震级), 　　6　　 after a famous seismologist, for these measurements．When an earthquake measures over 4.5 on the Richter scale, it is 　　7　　 enough to cause damage．Scientists have determined that a(an)　　8　　 is not likely to have a large 　　9　　 when many small quakes have been 　　10　　．When the small quakes stop, then pressure 　　11　　 and a strong quake is more likely．

　　There are several other 　　12　　 to predict earthquakes．Scientists can measure the tiny 　　13　　 in the tilt(倾斜)of the land that happen before earthquakes occur．Increases in the amount of radon(氡), a substance found in deep 　　14　　, as well as a high level of water in the wells, can also 　　15　　 that an earthquake is likely to occur．In addition, scientists have found that some animals, like dogs, behave 　　16　　 before an earthquake：they become 　　17　　 and howl(嚎叫)．

　　Seismologists have 　　18　　 predicted several earthquakes, such as the earthquake which occurred in Zhangjiakou, China in 1998．　　19　　, not all earthquakes are predictable, and a system for predicting is not yet 　　20　　．