阅读理解。
There were many beautiful buildings in ancient Rome, but the living conditions for ordinary people
were bad. Most of their homes were so poorly made that they fell down or were fire hazards (=danger) with their steep, narrow wooden stairways. Most people were packed into apartment buildings that
rose shakily (=unsafely) six to twelve floors above the ground. The apartments were rooms about three
metres square, and each building housed about five hundred people.
These tall buildings faced each other across streets only three metres wide, so no sunlight reached the ground. Even so, apartments were costly, though cheaper places could be had outside Rome. But people wanted to be near their work and entertainment. So the streets became crowded and it was hard to move quickly. At night, the streets were filled with noise as food and supplies were brought inthe city on wagons and carts.
1. In ancient Rome, most people lived in ________ apartments.
A. small and crowded
B. clean and tidy
C. spacious and sunny
D. tall and big
2. The streets in ancient Rome were ________.
A. crowded and noisy
B. wide and bright
C. narrow and dark
D. both A and C
3. People liked to live in Rome Because________.
A. the apartments were comfortable
B. the living expenses were low
C. they have no money to build houses outside the city
D. they wanted to enjoy the conveniences of the city
4. This passage is mainly about ________ in ancient Rome.
A. the beautiful buildings
B. the living conditions of ordinary people
C. the streets and transportation
D. the food and daily supplies
这种天然水，需先加入Ca(OH)2_______g，再加入Na2CO3_______g。