[Grammar] Off duty.

[Rollercoaster1]

Isn't "off" adjective in the following sentence?

To be off duty on Wednesdays.

 

[Rollercoaster1]

Is it not describing/modifying duty?

 

[bhaisahab]

No, it isn't. We could describe "duty" as "night duty", "guard duty", etcetera, but in "on" or "off" duty "on" and "off" are, as Piscean suggested, prepositions.

 

[Rollercoaster1]

And in this case? To be off-duty on Wednesday.

 

[bhaisahab]

"off-duty" is a compound adjective.