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a number of are is the most popular phrase on the web.

a number of is 11,420,000 results on the web	a number of are 18,710,000 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.	Many corporations and a number of NPIs are in this situation. When it comes to enlargement, a number of issues are particularly important. It is the case that a number of Members are considering appealing against this decision. A number of measures are needed in this regard. A number of obstacles are still preventing the single market from operating to its full potential. A number of derogations are provided, in particular when the third country provides adequate safeguards. A number of projects are currently in progress or under consideration. A number of vessels are moving toward the Neutral Zone.

a number of is

11,420,000 results on the web

a number of are

18,710,000 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.

Many corporations and a number of NPIs are in this situation.
When it comes to enlargement, a number of issues are particularly important.
It is the case that a number of Members are considering appealing against this decision.
A number of measures are needed in this regard.
A number of obstacles are still preventing the single market from operating to its full potential.
A number of derogations are provided, in particular when the third country provides adequate safeguards.
A number of projects are currently in progress or under consideration.
A number of vessels are moving toward the Neutral Zone.