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many years’ experience is the most popular phrase on the web.

many year experience 1106,000 results on the web	many years’ experience 112,500,000 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.	We have needed the many years' experience of negotiating between the Commission, the Council and the European Parliament. For example, a farmer who has many years' experience of transport and who transports his own animals further than 65 km must meet the same conditions as a professional transport entrepreneur. It is in the interests of the ESA and the consortium which won the contract to provide continuity of employment for highly skilled workers who have many years' experience in the provision of the service. He's a businessman of many years' experience. Seasoned operators with many years' experience should not have to prove a second time in an examination that they are professionally competent. My many years' experience confirms precisely that. Transport managers should be able to demonstrate either many years' experience or a high level of training. That's something you learn from many years' experience.

many year experience

1106,000 results on the web

many years’ experience

112,500,000 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.

We have needed the many years' experience of negotiating between the Commission, the Council and the European Parliament.
For example, a farmer who has many years' experience of transport and who transports his own animals further than 65 km must meet the same conditions as a professional transport entrepreneur.
It is in the interests of the ESA and the consortium which won the contract to provide continuity of employment for highly skilled workers who have many years' experience in the provision of the service.
He's a businessman of many years' experience.
Seasoned operators with many years' experience should not have to prove a second time in an examination that they are professionally competent.
My many years' experience confirms precisely that.
Transport managers should be able to demonstrate either many years' experience or a high level of training.
That's something you learn from many years' experience.