Many tall buildings ___(build)in our city during the last few years.

用现在完成时
have been built应用现在完成,应为是 对现在的影响,此外还有during

have been built
during the last few years指在过去的几年间，应用过去完成时
因为Many tall buildings是被建造的，所以应用被动语态

were being built

had been built
during the last few years 在过去一段时间段里，要用过去完成时
又因为高楼是被建的，所以要用过去完成时的被动语态

were built

have been built

不能用现在时态,因为人家明明写着during the last few years.
过去完成时也不对,没有一个过去的时间或过去的动作作参照,只有一个过去的时间,就是在这个时间内发生的动作所以应该用过去式,were built

Many tall buildings _have been built__(build)in our city during the last few years.