语法填空。

     At 3:42 a.m. everything began to shake. It seemed l_____ the world was 2_____ an end! Eleven kilometers

3_____ (direct) below the city the greatest earthquakes of the 20th century began. It was heard in Beijing,

4_____ is one hundred kilometers away. One-third of the nation felt it. A huge crack that was eight kilometers

long and thirty meters wide cut 5_____ houses, roads and canals. Steam burst from 6_____ (hole) in the

ground. Hard hills of rock became nvers of dirt. In fifteen terrible seconds a large city lay in ruins. Two-thirds

of the people died or 7_____ (injure) during the earthquake. Thousands of families 8_____ (kill) and many

children were left 9_____ parents. The number of people 10_____ were killed or injured reached more than

400,000.

剖视图按剖切面与观察者之间的部分移去的多少(即剖切范围的大小)，可分为全剖视图、半剖视图、局部剖视图三种。