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來回變化,從有趣的到錯誤的宣稱。

3、Multipolar pump. Polluted water pump. Move back and forth pump and jumping equipment.
可使用在循環(huán)水泵、多級泵、污水泵、往復式泵等有鼠動或跳動的設備上。

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

5、To move back and forth alternately.
往復運動交互地向后、向前運動