乘坐轻轨的缺点是投资巨大，周期长，收效缓慢;占用城市用地;影响生态环境，如噪音、震动、电磁辐射等;影响城市景观等。

A、地铁站

B、轻轨站

C、地道战

D、火车站

A、练习楼

B、操练楼

C、实用性楼

D、实训楼

What does this sign mean?

A、You may park (your car).

B、You mustn't park (your car).

C、You may pass (the road).

D、You mustn't pass (the road).

A、

B、

C、

D、

A、Hello, Miss. I'm looking for the City Library.

B、Sorry, I'm a stranger here. You may ask the policeman.

C、Walk that way for about 30 meters.

D、It's the second door on the right next to the meeting room.