A:不合理的国际经济秩序
B:南、北方发展的基础相差悬殊
C:南方国家历史上是北方国家的原料产地和市场
D:南、北方人口和资源分布不均
温度/℃
10
20
30
40
溶解度/g
氯化钠
35.8
36.0
36.3
36.6
碳酸钠
12.2
21.8
39.7
53.2
He had wanted to write ____children's book for many years, but one thing or another always got in _________ way.