--- Where are the students ? How could they keep us waiting for so long? --- They started an hour ago and they____ be here in fifteen minutes, I think.
I know only a little about this matter; you may ask ____ knows better than I.
This is the school ____ we visited three days ago.
This is the factory ____ we worked a year ago.
Nearby were two canoes ____ they had come to the island.
Jack is pleased with ____ you have given him and all ____ you have told him.