In 1988 a Soviet icebreaking ship elped free thregray whales that had become trapped in the Arctic ice aftre they 【had swam】 into the coastal waters of Alaska ot feed.
这里哪里错了啊。。。我是觉得swim这个动词发生在trap之前啊
啊= =竟然疏忽了这个。。。
那为什么之前用had become trapped啊?
had become trapped 所在句子是个定语从句吧,描述该动作发生在主句动词之前。
我认为是这样!
而且这里的trapped不是当动词,是形容词。