onkeyup and onkeydown for subtexts in a text

Ok, the scenario is:

I have a text box.. I want to fire "onkeyup" and "onkeydown" events in that textbox after i enter a space in it !

In detail:

I have to insert WORK_HOURS, PLACE_OF_WORK and DETAILS_OF_WORK in one textbox.(thats called Quick Insert mode of our project). Those 3 should be seperated by space. For example, consider i enter:

8.00 Germany Time manegement project

where,

8.00 --> WORK_HOURS
Germany --> PLACE_OF_WORK
Time manegement project --> DETAILS_OF_WORK.

(Note: I split the strnig in server side with no problem.)

what i want is: after i enter the first space (after "8.00") i need to fire onkeyup and onkeydown events till the next space(before "Time manegement project"). that is, i need to call onkeyup and onkeydown events for "Germany" in my example.

Hope that makes sense.