25. Welcome to the Historical Museum, everyone! This stone knife _______ in South Africa and experts can’t be exactly sure about its use.
Is it the years _______ you worked in Africa as a doctor _______ have a great effect on your literary works?
Young people who have got jobs may realize university lessons can’t be the only preparation for all of the situations ________ appear in the working world.
Today the public is much concerned about the way _______ .
It was in the factory _______ his friend worked _______ he picked up a lot of experience.
He’s got himself into a dangerous situation _________ he is likely to lose control over the plane.