Mary didn’t understand made her deskmate so upset all the morning.
A.it was that
B.why it was that
C.how that was
D.what it was that
网友回答
D解析本题考查强调句型。该题为特殊疑问句整体做understand的宾语，因此应该使用正常语序。由于made her deskmate so upset缺少主语，因此我们可以断定“被强调部分”是做主语的，因此应该使用疑问代词what。