用所给词的适当形式填空

① It's important for the children ____ (make) friends with others.

② The 31st Olympic Games ____ (hold) in Brazil.

③The ____ (discuss) went on for an hour this morning.

④ ____ (compare) with my homework, his is much better.

⑤ He is the first one to reach the ____ (finish) line in the running race.