He made three good friends in the university, ______ joined the army after graduation.
Some of you may have finished unit one. _____ , you can go on to unit two.
-Do you mind _____alone at home? -No, but I want a good book_______.
The headmaster wants to have the opening speech ________ by our math teacher next month.
It was ________ the trouble to explain a job fully to new employees.
He argued _______ smoking, and insisted that it was ________ argument that smoking was harmful to health.