Ⅰ.单句语法填空
1．Each group introduced their country's culture，advanced (advance) technology，environment protection and new green energy.
2．The attraction (attract) of the earth for other bodies is called the force of gravity.
3．Well preserved (preserve) as the car is，there is something wrong with its engine and wheels.
4．Beijing is filled with people from various (vary) parts of China.
5．The bridge being built now is 500 metres in length(long)．
