_________ caused the accident is still a mystery.
—We don’t have enough books .What would you like to ? —How about two of us one?
— What a mistake! — Yes. I _____ his doing it another way, but without success.
Do you think shopping online will________take the place of shopping in stores?
The man reassured us that all that was pure rumor and was ____ made up by some ill men.
Language can be defined as a tool by which human beings ________ with one another.