The heavy fog in London made ______deep impression on us, which was sometimes so heavy that we lost _______sight of everything around us.
__________ ups and downs in the past four years,Bob finally succeeded in extending his business overseas.
Some experts believe ________ our personalities are largely determined by genetic factors.
—Did you watch the live broadcast of China’s military parade on September,3rd? —It’s a pity that I missed it.I ________ to New York then.
When I asked if __________ would help me,Tony was the first to volunteer.
The hikers made marks on the way ________ they wouldn’t get lost in the mountain.