Suspended Compounds :


With a series of nearly identical compounds, we sometimes delay the final term of the final term until the last instance, allowing the hyphen to act as a kind of place holder, as in

The third- and fourth-grade teachers met with the parents.

Both full- and part-time employees will get raises this year.

We don't see many 3-, 4-, and 5-year-old children around here.

Be careful not to overuse this feature of the hyphen; readers have to wait until that final instance to know what you're talking about, and that can be annoying.