seesaws

1.跷跷板(戏)

2.上下动;前后动;动摇;变动

1.上下动地[的];前后动地[的];交互地[的];拉锯性地[的]

1.交替;(温度等)升降;涨落

2.玩跷跷板戏;一上一下地玩;上下动;前后动;动摇

1.a long board for children to play on, balanced on a support in the middle. A children’s word for this is teeter totter.

2.a situation that keeps changing, especially one that involves two opposite things that rise and fall many times

1.to change from one condition to another and back again many times, or to rise and fall again many times

2.to play on a seesaw