Manhattan SC p256 关于x times as...as/比较级

1.    关于倍数的表达----by balabaladou7：
白勇《GMAT语法全解》中说过“...times + 形容词/副词比较级 + than.....”属于有争议的结构，因为产生歧义。标准书面语中避免使用此结构。“....times + as+形容词/副词+as" 则常用。
但好像张道真语法上有说:--6道OG例子证明这个两种表达都可以。
five times as...as 和 five times more/greater than...是表达相同的数量概念的.这是英语国家的语言习惯,不能用中文硬翻理解. 张道真语法 P384/页尾注释

If you want to relate the quantities by multiplication, use times and as... as... together.

Right: The man is FIVE TIMES AS OLD AS his grandson.
Wrong: The man is FIVE TIMES OLDER THAN his grandson.

The first sentence means that the man's age = 5 x his grandson's age. In the second example, the author is technically saying that the man is six times as old as his grandson. This meaning is unlikely; the author probably meant "five times as old." In one GMAT problem (#72 in the Verbal Supplement), the correct answer says that certain numbers are "5 times greater than ... " other numbers. In general, however, this usage should be avoided.
Use times without as or than to indicate direct multiplication. (Twice means two times.)
Right: The cost of a ticket is $12, SIX TIMES the cost ten years ago.
Right: The concert was attended by 300 people, TWICE the previous attendance.

If you want to relate two quantities by addition or subtraction, use more than or less than.

Right: I am TEN years OLDER THAN you.
Wrong: I am TEN years AS OLD AS you.

The first sentence means that my age = your age + 10 years. The second sentence is nonsensical.
The words more and less are rather flexible. They can be used