13. --May I put my luggage on the seat beside you, sir?--__________.
— How long is it ______ you picked up your badminton training? — It was not until my finance became better in last December ______ I started the training.
The young teacher found it hard to _____ his explanation in class to most of the class.
—Tom, your lazy bone! You left the dishes unwashed again! —_______? Mom isn’t at home and she can’t hear you.
The driver was at _____ loss when ______ word came that he was forbidden to drive for speeding.
One of the most important things in education is to let students ____ positive emotions and experience in the process of their learning.