The library's study room is full of students _ for the exam A:busily prepared B:busy preparing C:busily prepare D:are bu
问题描述：
The library's study room is full of students _ for the exam A:busily prepared B:busy preparing C:busily prepare D:are busily preparing
答
选择：B: busy preparing
解析
可以从句子的结构分析进行判断：
主要成分：The library's study room is full of students（图书馆自习教室坐满了学生）
伴随状语：busy preparing for the exam【这是形容词短语,也可以改写为时间状语从句(while they are) busy preparing for the exam（与此同时他们正忙于准备考试）,其中用到了be busy doing sth（忙于做某事）句型】
【注】形容词短语可以用作伴随状语