问题
选择题
Mary seems _______ the bad news, for she looks nice and happy.
A．not to have learned
B．not to be hearing
C．not having learned
D．not to be
答案
答案：A
题目分析：考查不定式用法。不定式的完成式表示该动作发生在谓语动作之前，否定式是在不定式符号前面直接加not.句意：Mary似乎还不知道那个坏消息，因为她看上去很开心。故A正确。