1. 用本单元出现的单词或短语的正确形式替换画线部分，保持句意不变。

1. （1） It is OK to be 15 to 30 minutes late in some areas.
3. （2） In foreign countries, we need to respect local traditions.
5. （3） I entered a chess contest and finished third.
7. （4） He brought his chicken to the market.
9. （5） I met a childhood friend at the party.
11. （6） Some often throw a big party to observe Christmas here.
13. （7） Students are required to sit in the front of the conference hall.
15. （8） John, a tough man, cried like a baby when he got his lost son back.
17. （9） Jack, the owner of this house, introduced us to the other guests.
19. （10） Although this idea is very good, not everyone likes it very much.