3 Choose the correct form of be to complete the text.

Text Completion:

Hi. I 'm Bárbara and this is my sister Carla. She 's 15. We 're from Mexico. I'm in grade 7 and Carla's in grade 10. Our parents are Rosa and Bernardo. They're both from Guadalajara. Dad's an English teacher at a school in Culiacán. Mum 's a doctor at Médica Sur. It's a very big hospital here in Mexico City.