在自动闭塞区段，若机车信号机显示一个半黄半红闪光时其含义是什么？
题型：问答题 简答题
问题：
在自动闭塞区段，若机车信号机显示一个半黄半红闪光时其含义是什么？
题型：问答题 简答题
第二部分：阅读理解（共15小题;每小题2分，满分30分）
阅读下列短文，从每题所给的四个选项A、B、C、D中，选出最佳选项。
A farmer was put in prison. One day, he got a letter from his wife.
“I am worried about our farm,” she wrote. “It’s time to plant potatoes, but I can’t do all the digging by myself.”
The farmer thought over and then had an idea. He wrote to his wife, “Don’t dig the fields. This is where my gold is. Don’t plant potatoes until I come home.”
A few days later, the farmer got another letter from his wife. It said, “Two days ago, about ten prison guards came to our fields. It looked as if they were looking for something. They have dug our fields.”
The farmer wrote to his wife at once. “Now you can plant our potatoes.” he wrote.
46. Why was the farmer put in prison? ________.
A. Because he had done something wrong
Because he had a lot of gold in the fields
C. The writer didn’t say anything about why the farmer was put in prison
D. For nothing
47. The farmer told his wife ____ first.
A. not to dig the fields B.to dig the fields
C. to ask the prison guards for help D. to find the gold in the fields
48. Why did the prison guards dig the farmer’s fields?________.
A. They wanted to help the farmer B.Their leader ordered them to do so
C. The farmer asked them to do so D. They wanted to find out the gold
49. Why did the farmer ask his wife to plant potatoes at once ? Because _____.
A. their fields had been dug
B.the gold was found out
C. the prison guards asked him to do so
D. the prison guards were digging the fields