Overhead bridges are found in many parts of Nanjing, especially in places where traffic is very heavy and crossing the road is very dangerous.
The purpose of these bridges is to enable passengers to cross road safely. Overhead bridges are used in very much the same way as zebra crossings. They are more efficient although less convenient because people have to climb up a long flight of steps. This is inconvenient especially to old people. When passengers using a zebra crossing,  traffic is held up. This is why the government has built many overhead bridges to help passengers and to keep traffic moving at the same time.
The government of Nanjing has spent much money in building these bridges. For their own safety, passengers should be encouraged to use. They can’t risk their lives by running across the road. Old people may think that it is a little difficult to climb up and down the steps, but it is much safer than walking across the road with all the dangerous of moving traffic.
Overhead bridges serve a very useful purpose. Passengers, both old and young, should make it a habit to use them. This will prevent unnecessary accidents and loss of life.
What is the advantage(优点) of overhead bridges mentioned in this passage?

A．Taller trucks can pass under them.

B．Passengers can climb up and have a good view of the city.

C．They are safer for the passengers and keep traffic moving at the same time.

D．They are easier and more convenient for the passengers.

Why were overhead bridges built in Nanjing?

A．Because they stop traffic from being held up.

B．Because they provide an easy way for the drivers to cross the road.

C．Because they save money for the government.

D．Because they save time for the passengers.

Which of the following statements is true according to the passage?

A．Overhead bridges are found in every part of Nanjing.

B．Overhead bridges are found in the centre of Nanjing.

C．Overhead bridges are found in many parts of big cities in China.

D．Overhead bridges are found in places where traffic is heavy.

The underlined words “ a zebra crossing” probably mean _______.

A．a safe place across road for passengers to walk across the road

B．a wild animal from Africa that looks like a horse with black and white colour on its body

C．a safe place across a road for zebras to walk across the road

D．a safe place across a road for children to play a game.

What’s the writer’s attitude(态度)towards overhead bridges?

A．It is inconvenient for old people to walk across the road.

B．It is much safer for the passengers though climbing up and down the steps may be a little difficult

C．An overhead bridge is more beautiful than a zebra crossing.

D．To build overhead bridges is the business of the government.