Just as the experts _______ it, this kind of material is not natural, but man-made.

I ordered three tickets to the opening ceremony of the 2010 Expo, but none___________me by now

The traffic department has taken effective measures ________ the car speed in the town and ________ the traffic accidents.[ ]

In the 1990’s, many well-educated young people went to Hainan Island ____their jobs.[ ]

Everyone passed the exam.It _________ difficult.