It is thought that the escaped prisoner was back in custody.   (been)
=>The escaped prisoner is .............................................. recaptured.
John's flat was near enough for him to walk for work, so he had no reason to take a taxi.   (since)
=> ........................................................................., he had no reason to take a taxi.
By law, all rear - seat passengers are obliged to wear seat-belts. (have
=> By law, seat-belts ........................ by all rear-seat passengers