Through years of hard work, Mrs. Smith, who ____ as a secretary for five years, is general manager of the company now.
Leave your key with your neighbor _you lock yourself out one day.
You should report any incident, ______ minor it is.
Edison was a clever boy, and ______ he was fourteen, he had learned advance mathematics by himself.
I ______ to go on a diet, but the dishes at the party were simply impossible to resist.
Not until the teacher explained the importance of getting up early ______ we promise to come early.