--Are you going to visit the exhibition this afternoon?—I’m not sur.Perhaps I’ll find __ other time.
--- Who is the girl standing over there?--- Well, if you ______ know, her name is Mabel.
Children under 12 years of age in that country _____ be under adult supervision when in a public library.
--- Isn't that Ann's husband over there?--- No, it ______ be him---I'm sure he doesn't wear glasses.
Mr White____at 8:30 for the meeting, but he didn't show up.
I often see lights in that empty house. Do you think I ______ report it to the police?