单项选择题

Can earthquake be predicted Scientists are (1) programs to predict where and when an earthquake will occur. They hope to (2) an early warning system that can be used to (3) earth-quakes so that lives can be saved. The scientists who are (4) this work is called seismologists. The word seismologist is (5) from the Greek word seismos, meaning earthquake.
Earthquakes are the most dangerous and (6) of all natural events. They occur in many parts of the world. Giant earthquakes have been (7) in Iran, China, India, Alaska, and so on. Two of the biggest earthquakes that were ever recorded (8) in China and Alaska, which measured about 8.5 on the Richter Scale. The Richter Scale was (9) by Charles Richter in 1935, and compares the energy (10) of earthquakes. An earthquake that measures a 2 on tile scale can be felt but causes (11) damage. One that measures 4.5 on the scale can cause slight damage, and an earth- quake that has a reading of over 7 can cause (12) damage. It is important to note that a reading of 4 indicates a quake ten times as strong as one with a reading of 3.
How do earthquakes occur Earthquakes are caused by the shifting of rocks along cracks, or faults, in the earth’s crust. The (13) is produced when rocks near each other are pulled (14) different directions.
Earthquake (15) is in its infancy. Scientists have only a (16) understanding of the physical (17) that cause earthquakes. Much more research has to be done. New and more up-to-date (18) have to be found for collecting earthquake data and analyzing it. (19) , seismologists have had some success in predicting earthquakes. Several small earthquakes were predicted. While this is a small start, it is (20) a beginning.

Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C, and D on ANSWER SHEET 1.3（）

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