A double quotation mark (") is missing at the end of the string being echo-ed.
echo后面的字符串的末尾缺少一个双引号（"）。
To correct the error, add double quotation marks to the end of line 9.
要想纠正这个错误，应该在第 9 行末尾添加双引号。
Futures markets suggest that it may yet double again before the end of the year.
期货市场显示在今年年底前，它可能仍会翻一倍。
more than double their level at the end of last year.
该股目前价格较去年年底上涨了一倍多。
How to add a NODE to the end of a Double Linked List?
如何将一个节点添加到双链表的终结吗？
Thee editor thinks they can double the magazine circulation by the end of the year.
主编觉得他们能在年底把杂志发行量增加一倍。
It is really important we do our job until the end and win the double.
对我们来说，重要的是要坚持做好自己的工作，尽力去赢得双冠。
However at the free end, displacement is double and strain is zero.
在自由端，应力为零而位移加倍。
The firm plans to double the capacity before the end of the year.
公司计划在年底之前将生产能力提高一倍。
Double contour of the end plates.
终板呈双重轮廓征。
Double-click the "License. txt" file in the current directory to read the end-user license agreement.
在当前的目录（路径）中双击License.txt文档，阅读终端用户许可协议。
Double-click the "License. txt" file in the current directory to read the end-user license agreement.
在当前的目录（路径）中双击License.txt文档，阅读终端用户许可协议。
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