What do you think of rail transit?

For the growing urban population, it is very necessary to build rail transit. The construction of rail transit not only relieves the traffic pressure, but also provides a fast and convenient way for suburban residents to travel. For example, some time ago, there was a heavy rain in the city where the answer master was located, and many vehicles in the stagnant water section could not pass. Many people chose the subway because it was the closing time on Friday. According to news reports, the subway passenger flow increased by 654.38+million during the off-duty hours that day, which shows that people's demand for rail transit in a specific period is still particularly large. However, the construction of rail transit needs long-term consideration and planning, and it needs to be considered when the population reaches a certain scale, because the investment cost of rail transit construction, especially the underground part, is huge. In addition, after the completion, a lot of money and personnel are needed, and almost all rail transit needs to operate for several years before it can return to its capital, so the profit is slow. Therefore, whether a city needs to build a rail transit standard needs various investigations and studies.