The economy of Dallas, Texas, is strong and diversified .
A、inflatedC
暂无解析
Urban renewal programs strive to upgrade areas that are becoming slums.
The controls of most modern airplanes can be operated either manually or automatically.
ThefirstimportantexpositionintheUnitedStateswasheldinPhiladelphiain1876.
The Salk vaccine is a major factor in the fight to eradicate polio.
Some animals pant and sweat to speed evaporation of body moisture and thus cool themselves.
