Alternate - alternative
From Hull AWE
- The verb is always 'to alternate'. There is no verb '
- The noun in British English is always alternative. Although American English may talk of 'an alternate', you are advised never to use this in the UK.
- The problems with the use of these words is as adjectives.
- Alternative has the general meaning of '[offering] a choice' - strictly, to pedants, between two things, but nowadays often used for more than two. An examiner may offer students alternative questions in the paper - i.e. different titles on which they may choose to write. It is this sense in which the word is used as a noun: "You may go by train or by plane: which alternative do you prefer?"
- Alternate means 'by turns'. It can be illustrated by 'alternating current', with the -ing participle of the verb. Students may also see it on timetables, where there may be a lecture every second Tuesday, with a workshop on the alternate weeks.
Do not confuse these words - do not use one when you mean the other. If you mean 'switching between two things, or states' use alternate. Otherwise, AWE's advice is not to use alternate unless you are sure, with consideration, that you are right.