It could be learned from the teacher's eyes he was very satisfied with her performance.
A. that
B. whether
C. what
D. where
网友回答
(答案→)A. that
B. whether
C. what
D. where
解析：答案：A。考查主语从句。句意：从老师的眼里可以看出老师对她的表演很满意。分析句子结构可以看出，前面的it为形式主语，真正的主语为that引导的主语从句，that无意义，不作成分，但是不能省略。