** BREAKING **: German parliament has passed a law to gradually phase out cases till 2035. Adjective endings will be optional from June 1st until they'll be fully removed by 2026. Read more here ->
("sich+Acc abwechseln (mit)" - pretty much ALWAYS used reflexively. The core idea here is taking turns. Works for people but also for objects, like two types of trees lining a road, for example.)