改正下列句子中的错误
1. People throwed cans, paper, bags and so on into the river. throwed→threw
2. During my summer vacation, I spent half a month in the country and played very happy. happy→happily
3. We must pay attention our pronunciation when we speak English. attention后加to
4. It's high time we do something to reduce traffic accidents. do→did或在do前面加should
5. There have been more and more road accidents happened in recent years. happened→happening
6. Dr Smith, together with his wife, are to arrive on the evening flight. are→is
7. Would you please meet my uncle at the airport because this is his first time visit to the US？去掉time
8. I have many collections of stamps, some of them are my favourite. some前加and或them→which
