2) useless adj. 无用的，无效的
It’s useless doing ∕to do sth.
It’s useless complaining ∕to complain.
3）go through 通过，经过；经历，经受；浏览；用完，做完；检查
They went through many hardships during the war.
It would take long to go through all the articles.
In less than six months, he went through his savings of a lifetime.
{知识拓展}
get through 接通（电话）；做完 look through 浏览；查阅
see through 看透，看穿，识破 through and through 完全，彻头彻尾
