Tim Bowen gives phrasal verbs a good write-up in this handy article.
According to a recent news report, ‘Some doctors are complaining of cramp as a result of writing out so many prescriptions’. Here, to write out means to complete an official document by writing the necessary information on it. Apart from doctors, police and other officials often write things out, as in ‘The traffic warden was still writing my ticket out when I got back to the car’.
Write out can also be used to mean to write something again, usually in a more detailed way, as in ‘You’re going to have to write that essay out more neatly before you hand it in’.
Often used in the passive, write out can also mean to remove a character from a television or radio series by writing stories that do not include them, as in ‘Two of the soap’s leading characters were involved in separate legal proceedings and were temporarily written out of the show’.
If you write something up, you write a report, article and so on, using notes that you made earlier, as in ‘I’m planning to write the report up when I’ve gathered all the relevant information’. A write-up is an article in a newspaper or magazine that gives the writer’s opinion about something such as a new book, play or film, as in ‘Her new book has had some very positive write-ups in the national press’.
Usually used in the passive, write into means to include a particular feature in an official document such as a contract, as in ‘The right to cancel at one month’s notice is written into the contract’.