Recently I found the following phrase in an English guide book:
In all regions except Southeast Asia it can be seen that the higher the consumption of cigarettes, the higher the tobacco-related mortality rate.
My question is: shouldn't I put a verb in the end of each clause? This would be:
In all regions except Southeast Asia it can be seen that the higher the consumption of cigarettes is, the higher the tobacco-related mortality rate is.
Another example from the same book:
The more accurate your use of modifiers the better your writing will be.
I strongly want to put 'is' after the word 'modifiers,' what's the reason it is omitted? Is there any rule for this?
In case you wonder: it is a volume published by Academic English Press, so I assume this omission isn't a mistake. I just want to know why they omit the verb there, since I haven't come across such examples before.