His essay, ____many times,was brief and to the point,and therefore won the first prize in the writi

题目简介

His essay, ____many times,was brief and to the point,and therefore won the first prize in the writing competition.

A．polishing up

B．having polished up

C．to be polished up

D．having been polished up

题型：单选题难度：偏易来源：不详

having been polished up为现在分词完成式的被动式，作定语修饰essay。根据后面的内容可知，他的文章已获得了一等奖，而polish up (修改，润饰)应是在此之前，故用其完成式。句意为：他的文章，经多次修改后，简洁而又切题，因此在作文比赛中赢得了一等奖。