How ever hard tried nothing seemed to work.
问题描述：
How ever hard tried nothing seemed to work.
无论多么努力地尝试都没有用.
答
语法错误
tried的主语没有
how ever hard i had tried nothing seemed to work.
其实这是两个分句
根据nothing seemed to work的过去时态
可知努力是已经做出了的,所以用过去完成时作以区别