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\node[anchor=north west] (synhifst) at ([yshift=-0.3em]hifst.south west) {\textbf{better?:}};
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\node[anchor=west] (ref) at (0,0) {\textbf{人工翻译:}\alert{After} North Korea demanded concessions from U.S. again before the start of a new round of six-nation talks ...};
\node[anchor=north west] (hifst) at ([yshift=-0.3em]ref.south west) {\textbf{机器翻译:}\blue{In}\black{} the new round of six-nation talks on North Korea again demanded that U.S. in the former promise ...};
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