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My parents told me to look forward ___ road signs while walking on the street.
| A．seeing | B．to seeing | C．to see | D．see |
Garter Druse ___________ his being selected for the important task to his courage，devotion and knowledge of the area.
| A．led | B．owed | C．devoted | D．contributed |
---Isn’t it a surprise that I happened to meet Francis Mathews at the Christmas Party last week?
---If my memory serves me correctly, you _____ each other for exactly two years.
| A．hadn’t seen | B．haven’t seen | C．didn’t see | D．don’t see |
When it______air pollution, Beijing faces the three “C” s-----cars，coal and construction，which lead to Beijing's thick air pollution.
| A．refers to | B．comes to | C．happens to | D．speaks to |
______ it have been the failure to pick up directions from the ground control that caused the air crash?
| A．Must | B．Could | C．Would | D．Should |
The one concern for parents and students is _______ the student pursues their university education in a foreign country, the student will not have the opportunity to establish social contacts in China.
| A．that | B．that if | C．whether | D．how |