In Nouns^x, Hyphens^x, Genitives^x

Grammar Geek wrote: If you use it before a noun, use the hyphens. Afterward, there will be a ten minutes question-and-answer session. Hi GG Afterward, there will be (a) ten minutes' question-and-answer session. Afterward, there will be a ten-minute question-and-answer session. Many people...

However, in quantitative expressions of the following type there is possible variation: a ten day absence With temporal nouns in the plural, the apostrophe is sometimes omitted: several weeks'/weeks vacation Pages 325 &1333, A Comprehensive Grammar of the English Language, by...

Hello Mara This is not an answer to your question. This is just a comment on the question you raised. All of what you are asking is exactly the things that have annoyed me long time since I began studying English. Some native speakers grudge that we ESLs are bad in using compound noun phrases....