问题补充：
Seeing the teacher the classroom, the boy pretended the text.
A. walking in; to read
B. coming in; reading
C. entering; to be reading
D. entered for; to have read
答案：
A. walking in; to read
B. coming in; reading
(答案→)C. entering; to be reading
D. entered for; to have read
解析：考查分词补足语和不定式用法。第一空考查了see sb doing sth看见某人正在做某事；本句中的the teacher与enter之间存在着主动关系，故使用现在分词的形式。第二空考查了pretend to do sth假装做某事；如果事情是正在发生的事情，就使用pretend to be doing sth假装正在做某事；句意：看见老师进入教室，孩子们假装在读课文。故C正确。
