英语语法中关于倍数问题怎么学啊 请教！！

1."A + be + 倍数 + as + 计量形容词原级 + as + B".
This tree is three times as tall as that one. 这棵树是那棵树的三倍高。
His father is twice as old as he. 他父亲的年纪有他两倍大。

2."A + be + 倍数 + 计量形容词比较级 + than + B "
The Yangtze River is almost twice longer than the Pearl River.
长江差不多比珠江长两倍。
The dictionary is exactly five times more expensive than that one.
这本字典比那本恰好贵5倍。

3."A + be + 倍数 + the + 计量名词 + of + B "
The newly broadened square id four times the size of the previous one.
新扩建的广场是未扩建时的四倍大。

4."The + 计量名词 + of + A + be + 倍数 + that + of + B "
The size of the newly broadened square is four times that of the previous one.

一般是times或者multiply表示倍数