A new railway is being built in this city. 这个城市正在修建一条新的铁路.（现在进行时）
The new railway has already been built.新铁路已经建成了.（现在完成时）
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以下为赠品~O(∩_∩)O~
You are wanted on the phone . 有你的电话.（一般现在时）
The railway was built in 1998. 这条铁路建于1998 年.（一般过去时）
The railway was being built this time last year.去年这个时候这条铁路正在修建.（过去进行时）
The new railway had been built by the end of last year.这条铁路在去年年底前已经建成了.（过去完成时）
A new railway will be built in this city next year.这个城市明年将建一条新的铁路.（一般将来时）
