The wreckage of something like a jet plain discovered in the heart of the desert is believed ______ a UFO and _______down for reasons still mysterious.
The small fishing village has ______ into a modern city in thirty years.
Mr. Keller ______ forty cigarettes a day until he gave it up.
--- Do you know that man? --- Not really, just a nodding _______.
Please remember _____ wins you respect is not your background but your knowledge and virtues.
I find it astonishing that she _____ treat you like this in public.