Many people agree that ______ knowledge of English is a must in _______ international trade today.
The thief had himself _____ by the police when he was trying to break into the hotel.
The reason was _____ I was busy with my work at that time.
. He misunderstood _____ I said.
. The trouble is _____ we are short of hands.
The guide showed the travelers _____ of the factory.