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for the reason is the most popular phrase on the web.

on the reason 1342,000,000 results on the web	for the reason 1343,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	but not for the reason that most of us think. Yes, but not for the reason you think. If we were to suspend all the programmes without exception for the reason given by a number of speakers here, we would be doing our environment more harm than good. But not for the reason you might think. But not for the reason everyone thinks. Why? Not for the reason that she thinks. But not for the reason you surmise. for the reason specified in paragraph 1

on the reason

1342,000,000 results on the web

for the reason

1343,000,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

but not for the reason that most of us think.
Yes, but not for the reason you think.
If we were to suspend all the programmes without exception for the reason given by a number of speakers here, we would be doing our environment more harm than good.
But not for the reason you might think.
But not for the reason everyone thinks.
Why? Not for the reason that she thinks.
But not for the reason you surmise.
for the reason specified in paragraph 1