Though it is 30 years ____ we last met, I still remember the scene _____ we got separated on a rainy day.
Edward, you play so well. But I ______ you played the piano.
She brought with her three friends, none of ______ I had ever met before.
I tried phoning her office, but I couldn't ______ .
His sister left home in 1998, and ______ since.
What do you mean, there are only ten tickets? There ______ be twelve.