问题
选择题
--Alice, why didn't you come yesterday?
--I _________, but I had an unexpected visitor.
A．had
B．would
C．was going to
D．did
答案
C
当不定式在某些结构后作复合谓语时，不定式符号 to后的内容可以省略。常见的结构有：be able to，be going to，have to，ought to，used to等。