问题补充：
The newly-built lab is the old one.
A. three times so big as
B. as three times big as
C. three times bigger than
D. three times the size
答案：
A. three times so big as
B. as three times big as
(答案→)C. three times bigger than
D. three times the size
解析：考查倍数的表达：句意：新建的实验室是旧的三倍。这里用的倍数的表达是：倍数+比较级+than的结构，表示倍数的词放在最前面，所以B错误，A错误，因为在肯定句的时候，用as as，否定句的时候采用not so as，D项使用倍数+名词+of的结构，这里少介词of，选C。
