Вот заполненные ответы на вопросы:
1. Religious holidays can become national ones in some countries, *can't they*?
2. Foreigners make friends slower, *don't they*?
3. In Britain people don’t congratulate each other on national holidays, *do they*?
4. National holidays and celebrations must unite people, *mustn't they*?
5. It is a bad idea not to queue in line, *isn't it*?
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