曼哈顿语法有一句话不理解哈~

echoqian1217

By January 2,2000, the so-called "Y2K problem" was already widely considered a joke— although the reason for the non-event was the huge corporate and governmental investment in prior countermeasures.
曼哈顿第九章讲——dash的时候提到的，是正确的句子，我不明白的是破折后后面的although不是一个完整的句子呀， 感觉只是一个从句，读起来总是挺奇怪的，还是破折号后面的东东形势比较灵活，什么都可以？