Ответы
1)
1. am / am not
2. is / isn't
3. are / aren't
2)
Jacob is watching
Mum and dad are flying to Spain
Your cat is sitting on my bed
Dad is practising the guitar
We are running in the park
The bus is stopping near the shops.
3)
She's writing an e-mail
They're playing basketball
He's doing an exam
He's going to bed
They're watching a film
It's swimming in the river
4.
They're not listening to music
We are eating dinner at home
She is playing tennis in the park
We aren't studying snakes at school
You aren't writing an email in English
They're visiting some friends
He isn't looking at the teacher.
5.
Ruby and Sue are watching Ross and Jack
Sara is sleeping
Dan is reading
Dan isn't sitting
Tom is running
Ruby isn't playing
Ross and Jack aren't playing basketball
Amy isn't running