___on-going division between English –speaking Canadians and French-speaking Canadians is _______major concern of the country.
Some insects ______ the color of their surroundings to protect themselves.
The living room is clean and tidy, with a dining table already ______ for a meal to be cooked.
Sam _____ some knowledge of the computer just by watching others working on it.
That’s the new machine ______ parts are too small to be seen.
—Do you think you could do without help? —______. This is not the first time for me.