has 是什么时态

His quality of life has improved dramatically since the operation.

手术后他的'生活质量大大改善了。

A new system has been devised to control traffic in the city.

控制城市交通的新系统已经设计出来。

The company has a long tradition of fine design.

这家公司的优秀设计历史悠久。

The country has a poor record on human rights.

这个国家人权记录不佳。

The information has been placed in the public domain.

这资料不受版权保护。