■ back

作为副词，要注意它究竟是管后面另一个状语成分的，还是同前面（例如动词）结合或是修饰前面动词的。

• Now he was back.现在他回来了。
• He had no idea how anxious his wife was back in Mexico.他不晓得他妻子在墨西哥老家是多么的着急。
• There are no dusty cassette-tape fragments among the ancient bones, for example, to tell us how language was back in the early stages. (George Yule, The Study of Language, p.1)古代骨骼堆中，又没有带尘土的录音带碎片来告诉我们，在那些远古时代，语言是怎么样的。

又例如：

• For one night, New York City was as it was back before air conditioning.纽约市有一夜简直就像昔日没有发明空调之前那样子。

这四句都有 was back，但是在第一句中，back 同前面的 was 直接结合；在后三句中，back 同前面的 was 没有直接关系，是用来加强后面时间状语的“老家”或“昔日”的意义。back 同后面的状语连在一起，还有另外一个意义，就是相当于 again，表示“重新如何如何”。

• US security company Blackwater was back on the streets of Baghdad on Friday.美军“黑水连”星期五又重新出现在巴格达街头。
• The wound did not hit any major arteries or bones and he was back in the fight within two weeks.伤势没有触及任何主要动脉或骨头，于是过了两周，他又重新参加战斗。