单项选择题
A.中国和美国都将为自身利益而努力改善和促进两国关系的进一步发展。 B.中美两国都将从改善了的和进一步发展的关系中获益。 C.中国和美国关系改进和进一步发展会有益于两国。 D.中国和谋取更多利益的美国进一步发展关系都是双方愿意的。
A.demand for cotton had decreased B.crops became varied C.planters grew richer D.soil was less productive
A.Planters had to buy more machines. B.The land in the west became more expensive than before. C.Planters had to pay more money to ship cotton. D.Planters needed more and more slaves.