B 人口的比较用大小,价格的比较用高低,
比较中要用到四个代词,
that ,those 是特指,其中 that指代单数,those指复数
one ,ones 是泛指,其中one 指代单数,ones 指代复数
例如：1.The weather in Nanjing is warmer than that in Beijing .
2.The students in Class One is more than those in Class Two .
3.A house made of brick is stronger than one made of wood .