A participant in one of my workshops, D. Hom, asked a question about hyphenating expressions such as “end of year.”
Determining what to hyphenate depends on whether the adjectives appear before or after the noun. If the sentence reads, “These are the end-of-year returns,” then the hyphens are necessary; if the sentence reads, “These are the returns for the end of year,” then the hyphens are unnecessary.
As the saying goes, “Punctuation is to writing as intonation is to speaking”; therefore, read your sentences aloud and you will hear yourself squeezing together the words requiring hyphenation. Do you hear the difference in the hyphenated and non-hyphenated italicized words below?
I work full time.
I am a full-time employee.
She has had a tenure of ups and downs.
She has had an up-and-down tenure.
The election was an opportunity that came to President Obama once in a lifetime. The election was a once-in-a-lifetime opportunity for President Obama.