题目内容：

The 2016 Summer Olympics was a major international sport event held in Rio, Brazil, (巴西里约) from 5 August to 21 August 2016.

More than 11,000 athletes took part. With 306 sets of medals, the games had 28 Olympic sports, including rugby sevens（7人制橄榄球） and golf, which were added to the Olympic program in 2009. These sporting events took place at 33 sports centres in the host(主办) city.

On 2 October 2009. Rio became the first South American city to host the Summer Olympics. These were the first games to be held in a Portuguese（葡萄牙语）-speaking country.

Some problems happened during the Rio Olympics, including the management of the country's government; health and safety problems and terrible pollution in the Guanabara Bay(海湾); and a doping scandal（吸毒丑闻） about Russia, which has affected the attending of its athletes in the Games.

The USA was on the top of the medal form for the fifth time in the past six Summer Olympics, winning the most golds (46) and most medals overall (121), as well as its 1,000th Olympic gold medal overall. The UK finished second and China finished third. Host country Brazil won seven gold medals, its most at any single Summer Olympics, finishing in thirteenth place.

根据上面的短文内容填空

1.The 2016 Summer Olympics was a major ____________________ held in Rio, Brazil, from 5 August to ___________________.

2.There were ___________________ 11, 000 athletes who took _____________ the Rio Olympics.

3.__________________ were added to the Olympic program in 2009. Rio became the first ______________________ to host the summer Olympics.

4.Some problems included the management of ______________________, and the Guanabara Bay was ____________________.

5.The USA was ___________________ of the medal form and _______________ finished third.