Choose the correct words.In the past,blind people (1) couldn039;t/mustn039;t read books-other

Choose the correct words.
In the past,blind people (1) couldn't/mustn't read books-other people (2) must/had to read to them.That changed with the invention of Braille.Now,blind people (3) can/have to read any book they want,so they (4) mustn't/dont have to depend on other people.They just (5) cant/have to learn the Braille alphabet.People who (6) cant/must see well can also listen to audio books.