A．Nobody knows for sure whether oil prices will go up or down in the future.
B．China’s increasing demand led OPEC to miscalculate production capacity.
C．There has been little gains in average fuel mileage efficiency.
D．The world will depend more on the Persian Gulf in the future.

A．All the shining silver coming from the mines should not be made into coins.
B．Art would play a role in uniting different peoples and in avoiding war.
C．A vulgar man will become a gentleman once he steps into a beautiful house.
D．The Chinese workman’s cup was more beautiful than cups in big hotels.