Scientists say it may be a few years ______ it is possible to test the new medicine onpatients.

.—-I’d like a cup of black coffee. What about you, Maggie— I prefer coffee______ sugar.

He won with his work ______ nothing had happened.

－Smoking isn’t allowed in public. Do you know the news－Yes, and I also helped to the signs in the street last week.

He is the only one of those clerks ________ to the important conference.