表示倍数
1. 倍数+as +形容词/副词(原级)+ as。如：
This bridge is three times as long as that one.这座桥是那座桥的三倍长。
2. 倍数+形容词或副词的比较级+than。如：
This bridge is three times longer than that one.这座桥是那座桥的三倍长。
3. 倍数+ the size/length/weight…+of+表示比较对象的名词。如：
This bridge is three times the length of that one. 这座桥是那座桥的三倍长。
4. 倍数+what引导的从句。如：
The college is twice what it was 5 years ago.这所大学是它五年前的两倍。
