Are these sentences correct?

  1. He can’t afford to buy this car because he has just retired from work and he has run out of money.
  2. She has cut down on the sugar intake because she want to lose weight.
  3. Her family have been furnishing her flat for a few months because she can’t stand living in an empty flat.
  4. She has been putting her pocket money by for two months to buy herself a nice dress.
    Thank you for your time!

They’re OK. I would change ‘the sugar intake’ to ‘her sugar intake’ in sentence 2.