问题
选择题
—— Nacy＿＿＿＿＿＿＿＿＿ the letter from her mother.
—— No, she can’t have. The postman hasn’t come yet.
A．can receive
B．can have received
C．must have received
D．must receive
答案
答案：C
“must have done”结构，表示对过去发生情况的肯定推测。