Which of the following best expresses the main idea of the passage?
（A）Trains helped pioneers to cross the Rocky Mountains.
（B） Railroad played an important role in American history.
（C） Trains controlled American economy in the 19th century.
（D） Railroads grew rapidly between 1865 and 1900.
参考答案
继续答题：下一题
更多大学英语单项选择题库试题
- 1— I will come to attend your lecture at 10:00 tomorrow.-考察时态 — I'm sorry, by then my lecture will have ended and I ____ my guests in my office.
- 2John helped me write a letter ____ English.用某种语言说/写/唱 均使用介词 in
- 3— Hello, could I speak to Don please — ___________
- 4No one can possibly recall any detail about the meeting．It is at least five years since it_.通常情况下since引导的句子后面用一般过去式
- 5It is necessary that this machine-tool _______ every day.
