1、And what happens if you want to move back and forth between a bunch of different letters?
如果你想閱讀，不同的書(shū)信呢？

2、Some self sealing argument move back and forth from interesting to false claims.
有些自我封閉式論點(diǎn)來(lái)回變化,從有趣的到錯(cuò)誤的宣稱(chēng)。

3、Multipolar pump. Polluted water pump. Move back and forth pump and jumping equipment.
可使用在循環(huán)水泵、多級(jí)泵、污水泵、往復(fù)式泵等有鼠動(dòng)或跳動(dòng)的設(shè)備上。

4、They may move back and forth between the U.S. and the home country.
他們可能在美國(guó)和自己的祖國(guó)之間搬來(lái)搬去。

5、To move back and forth alternately.
往復(fù)運(yùn)動(dòng)交互地向后、向前運(yùn)動(dòng)