zhang太太
保持平衡balance ['bæləns]n. 平衡；余额；匀称vt. 使平衡；结算；使相称vi. 保持平衡；相称；抵销keep balance/keep one's balance保持平衡keep ecological balance:保持生态平衡/维护生态平衡/坚持生态均衡例句：1.海豚用鼻子顶著球，使其保持平衡。The dolphin balanced the ball on its nose.2.她保持平衡，平稳地骑着自行车。She kept her balance and rode the bicycle.
