【判断题】Block systemis a kind of train operation,whichmeans when a section isoccupied by a train and no other train is allowed to use that section until the proceeding train has traversed that section.
【单选题】Which of the following is the correct order of problem-solution pattern?① Give your Solution② Inquire for the answer to the question.③ Tell a personal experience and ask a question accordingly.④ y...