His eyes suddenly widened. I knew a good idea must have _________ to him.

Suzy’s jeans are the same______ Anna’s but different_______ Elsa’s.

scientists have done a lot of research on A (H1N1) flu, there are still some cases for further study.[ ]

When did you go to bed last night, Tom?—-At 10 pm. But my mother___________,

.—I can’t find Mr. Smith. Where did you last see him this morning?—It was in the hotel _______ he stayed.