In a word,I think he is a fool.
In a word, he's useless.

word by word：逐渐的，慢慢的； 逐字逐句的。
例句：Bombarded with information from our electronic devices, it would be imp搜趣网ossible to cope if we read word by word, line by line.
翻译：我们的手机、电脑每天都会被海量信息所轰炸，逐字逐句的阅读显然是不可能的。

word to know 造句：
英语：It seems a gargantuan task to teach a pupil to memorize every (word) he needs (to know), much as if the child were being asked to shovel a huge pile of sand, with tjrxrOkheshovel shut away.
汉语：教一个小学生去死背他//www.souquanme.com们需要掌握的每一个单词，看来真jrxrOk是一项浩繁的任务，就//www.souquanme.com像要一个孩子铲掉一大堆沙子，却不给他铲子。