Collocations for productive - adj.

be, prove, seem
Internet sources have proved extremely productive.

feel
It makes them feel productive even if it is not a paying job.

become
make sb/sth
Daylight makes people more productive.

do sth
I just wish he would do something productive with his life.

remain, stay
The bush must be pruned to remain productive.

extremely, fairly, very, etc.
enormously, exceptionally, highly, incredibly, remarkably
It was a highly productive meeting.

potentially
consistently
economically
economically productive workers

Productive is used with these nouns:
avenue, capacity, citizen, force, investment, labour, manner, meeting, partnership, worker