Question of the Day #868

By today, the day of her funeral, millions will have spent long hours, twenty-two, in some cases, in queues, stretching to five miles, patiently waiting to file into Westminster Hall, where the queen’s coffin lies in state, to pay their last respects.

From the 10th paragraph of this article at the KT Press.

  上記の文で、file intoの意味は？
In the sentence above, what does "file into" mean?

  答えは、コメントに書いてください。
Write your answer in the Comments.

明日、ここに答えを書きます。
I will add the answer and other remarks here tomorrow.

 

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