问题补充：
The book is that one.
A. as three times long as
B. three times the length of
C. three time as long as
D. three times as longer as
答案：
A. as three times long as
(答案→)B. three times the length of
C. three time as long as
D. three times as longer as
解析：句意：这本书是那本书的三倍长。这里使用了倍数的表达“倍数+the+名词+of…”，A项应该是three times as long as ，C项应该是time应该是复数，D项long是原级，选B。
