Complete the sentences with the correct form of the verb 'to be':
1. Anna ___ at the zoo.
2. Nikita ___ put on a T-shirt for school.
3. Liza ___ had 20 candles on her cake.
4. Olga ___ had a good time at the zoo.
5. She ___ have a good time at the zoo?
6. Oleg ___ rode a bike last night.
7. Lena ___ went to the museum on Monday.