周末我们租了一辆双人自行车，沿着湖边骑行。

We rented a ___tandem for the weekend and rode it along the lake.

老师和家长需要共同努力来帮助孩子成长。

Teachers and parents need to work in ___tandem to help children grow.

他们骑着双人自行车并排在乡间小路上。

They rode their ___tandem bicycles side by side on the country road.