1 They can't buy a television set because they have spent all their money .
2 The man has spoken for more than two hours.
3 The police has watched him for several weeks.
4 I have loiled some water for your tea.
5 They look tired.You have worked in the fields.
6 I have waited for an hour for that bus and now I'm going home.
现在完成时说白了就是have/has+过去分词