back and forth

来回地； 反复地

You can imagine a bead with a wire going through it and the bead can only slide back and forth.(你可以想象一个有金属丝穿过的珠子而且这个珠子只能前后滑动。)

He continued walking back and forth, muttering to himself; he had forgotten the King entirely.(他不断地走来走去，喃喃自语；他完全忘记了国王。)

The pendulum swings back and forth.(这就像单摆一样来回摆动。)

The prosecution and defence were bandying accusations back and forth.(原告与被告你来我往，互相指责。)

If two flying insect populations took up residence in separate nearby valleys, chances are that individuals from each population would fly back and forth, continuing gene flow.(如果有两个飞行昆虫种群居住在相距不远的不同山谷中，那么任一种群中的个体都有可能来回飞行，从而使基因流动继续。)

The people swayed back and forth with arms linked.(人们手拉手前后摇摆着。)

She passed the needle through the rough cloth, back and forth.(她用针在那块粗布上来来回回地穿进穿出。)

They continue calling back and forth until they all find each other again.(他们不停地来回打电话，直到他们再次找到彼此。)

From what I remember, water changes back and forth from water in lakes and oceans to vapor, and then back to water again when it falls as rain or snow, as precipitation.(根据我的记忆，水往复地变化，从湖泊和海洋里的水变成水蒸气，然后当它以雨或雪——也就是降水的形式落下时又变成水。)

So energy can go back and forth.(所以能量可以来来往往。)

adv

1. moving from one place to another and back again

e.g. he traveled back and forth between Los Angeles and New York
the treetops whipped to and fro in a frightening manner
the old man just sat on the porch and rocked back and forth all day

Synonym: backward and forwardto and fro

1. 来回地,反复地：at times 有时,间或 | back and forth 来回地,反复地 | back of 在......后面

2.

2. (前后)来回地,往返：attend to 专心;照顾,护理 | back and forth (前后)来回地,往返 | back away 逐渐后退

3. back and forth在线翻译

3. (前后)来回地,反复地：at the same time同时;然而,不过 | at the sight of一看见......就 | back and forth(前后)来回地,反复地