He insisted that we ________ rest until we finish the work.
Wang Pin is an advanced worker in our company. He _______ for four years in Yangzhou University.
When it______ air pollution, Beijing faces the three “C” s-----cars,coal and construction,which lead to Beijing's thick air pollution.
______ it have been the failure to pick up directions from the ground control that caused the air crash?
The one concern for parents and students is ______ if the student pursues their university education in a foreign country, the student will not have the opportunity to establish social contacts in China.
Not until the train pulled into the next station ______ her suitcase gone.