Air bags for cars were invented _____ li
题型:选择题
问题:
Air bags for cars were invented _____ lives. Without them more people would be injured in car accidents.
A.saving
B.saved
C.to save
D.to have saved
Air bags for cars were invented _____ lives. Without them more people would be injured in car accidents.
A.saving
B.saved
C.to save
D.to have saved