Looking on the internet deeply has found these results:

A large portion is is the most popular phrase on the web.

A large portion are 134,200 results on the web	A large portion is 1222,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Leaving a large portion of our military's defenses blind. Though her father paid for a large portion. Given the relatively low anti Leaving a large portion of our military's defenses blind. Deck is still decompressed. A large portion of E A large portion of nitric oxide for inhalation is absorbed systemically. dumping duty level and the fact that a large portion of Chinese imports are not subject to measures also makes it unlikely the measures in force would be the determinant factor for the alleged relocation of the downstream industries.	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

A large portion are

134,200 results on the web

A large portion is

1222,000 results on the web

More popular!

Leaving a large portion of our military's defenses blind.
Though her father paid for a large portion.
Given the relatively low anti
Leaving a large portion of our military's defenses blind.
Deck is still decompressed.
A large portion of E
A large portion of nitric oxide for inhalation is absorbed systemically.
dumping duty level and the fact that a large portion of Chinese imports are not subject to measures also makes it unlikely the measures in force would be the determinant factor for the alleged relocation of the downstream industries.

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