Alright, this is the translated version of the article (by me, so I hope you can understand):
For the past years a guy named Valentijn Kuperus has been in an airplane for 30 to 50 times a year on average. He has been in 60 different countries and does this all on his student budget! Before this interview, he has slept a night in a hotel in Amsterdam for 40 euro so that he can stay for free at a deluxe hotel at Bora-Bora where one night costs around 200 euros.
How does this work?
In exchange for an amount of points, you get flight tickets from the airline. You have to exploit this offer as good as possible. Lets say you can pick an intercontinental flight; you could choose to fly from Amsterdam to Frankfurt. But, you can also choose to fly from Miami to New York to Vancouver to Alaska. By making use of software owned by travel companies these flights are found. Usually the guy books his trips one year before departure. In February he goes to Vancouver, in March to Guatemala, in April to Singapore, in may to Sidney, in June Abu Dhabi and in July he goes to 6 destinations; Tokyo, Ishigaki, French-Polynesia, Boracay, Cambodja and Vietnam. All of this on his student budget! (which, in Holland, is usually not higher than €400-500,- per month.)
He has been in 67 countries so far and because of all the stamps in his passport, he has to get a new one every 2 or 3 years.
This was my translated version of the article, I hope you guys can understand how he's doing it cause I don't

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