听下面一段材料,回答第1-3题。 |
1. When was it unusual to see a plane? |
A. In the early 1960's B. In the 16th century C. In the early 1900's |
2. Why can we use electric lights? |
A. Someone has paid for us. B. We have more money than before. C. Someone invented ways to make use of electricity. |
3. What are the speakers talking about? |
A. The changes of life. B. The history of planes. C. The invention of electric lights. |