Below are taken from a grammar book.
a) The Earth is about **four times as big as** the moon. = The Earth is about **four times bigger than** the moon. b) The Earth is about twice as big as Mars. ≠ twice bigger than.
If (a) is correct, then how come I cannot use twice in the same way in the example (b)?
I have taken a look at
Especially on the second link I can totally understand the logic and I agree. But in these examples, it is size and I cannot really figure out why. The last example being;
c) That cable is only **half as long as** this one. ≠ half longer than.
On this last example, I can totally understand why it is not equal. But when it comes to (b), I simply cannot explain. Aren't twice and two times are same things?
While searching I also found this; Does this ‘twice’ mean two times, or double in quantity?
There is a difference between something being "two times longer than...." and "two times as long as... " Say something is 10 ft.
If above statement is true then how come (a) is correct? A clarification would be great as I am having a terrible headache because of this.