选择性必修第四册Unit 51. bounce vi./vt.(使)弹起;上下晃动 n.弹性，弹跳，活力 bounce around 蹦来蹦去，弹来弹去翻译：很多人只是有一些想法在脑子里晃来晃去。_____________________________________________________1. bounce back__________e.g. It will take time for our economy to fully...