明沟系统
参考答案：
是采取街沟或晓得明沟汇集雨水，然后由相应大小的明沟集中排入天然水体的排水系统。
---How is the old lady? ---____.
A．she is fifty.
B．She’s a nurse
C．She’s much better
D．She’s Mrs white
He finds watching movies _____ because the people in the movies speak too quickly to understand. [ ]
A. frustrated
B. excited
C. exciting
D. frustrating
