Find one mistake in each sentence and correct it.
1. In Vietnam, you shouldn’t drive on the left; otherwise, you will be fined.
2. When I was watching TV, there is a sudden power cut.
3. Although the ceremony started too late, I couldn’t join it.
4. They were playing computer games at 9 p.m. one day ago.
5. Does she has to pay extra for the overdue book?