1. It is not necessary to have experience to do the job. -> You don't have to have experience to do the job. (Используем 'don't have to' для выражения отсутствия необходимости).
2. It is obligatory for doctors to wash their hands. -> Doctors must wash their hands. (Используем 'must' для выражения обязательства).
3. It is a good idea for journalists to learn a foreign language. -> Journalists should learn a foreign language. (Используем 'should' для выражения совета).
4. In our school, we are not allowed to run in the corridor. -> In our school, we mustn't run in the corridor. (Используем 'mustn't' для выражения запрета).
5. It isn't a good idea to use informal language in a job interview. -> You shouldn't use informal language in a job interview. (Используем 'shouldn't' для выражения совета против чего-либо).
6. It is not obligatory for students to wear a tie here. -> Students don't have to wear a tie here. (Используем 'don't have to' для выражения отсутствия необходимости).
7. It is essential for firefighters to stay calm. -> Firefighters must stay calm. (Используем 'must' для выражения сильной необходимости/обязательства).
Ответ:
You don't have to have experience to do the job.
Doctors must wash their hands.
Journalists should learn a foreign language.
In our school, we mustn't run in the corridor.
You shouldn't use informal language in a job interview.