持续的大雨逐渐侵蚀了河岸的根基。

The constant heavy rain has ___undermined the riverbank's foundation.

持续的谣言逐渐损害了他在公司的声誉。

The persistent rumors ___undermined his reputation in the company over time.

他的不负责任的行为损害了团队的士气。

His irresponsible behavior ___undermined the team's morale.