1. Mandy read the instructions.

doesn't have to
don't have to

2. Mum make sandwiches.

doesn't have to
don't have to

3. She work late.

doesn’t have to
don’t have to

1. Doesn’t have to(так третье лицо)
2. Doesn’t have to (третье лицо)
3.doesn’t have to (третье лицо)