Investigations ______ the origin of life on the earth have shown that, given earth-like conditions, the formation of life is almost inevitable.

Our high school has an assembly_______ 2 weeks.

I’d like to _______ this old car for a new model , but I can’t afford it.

Man has never ceased to search for cures for such ________ diseases as cancer and AIDS.

Sometimes she feels very depressed , as if tomorrow _______ come.

The key to ________laws lies in devotion and responsibility of the staff concerned.

People ________ a new festival so that African Americans would be able to celebrate their history and culture.

George is one of the brightest who_________ from New York University.

George is one of the brightest students who_________ from New York University.