—–I think the man over there must be Tom.—–It _____ be him. He has ______ to America.
--_________ to the United States? --No, never, but I went to Canada a few years ago.
It's________ far_______ walk home from here. Let's take a bus.
They really don’t know how _________ the difficult problem.
They used to be friends, ______?
It has been many years ________ we met at the train station in 2008.