Collocations for certain - adj.

be, feel, look, seem
Digby looked certain to be the next president.

become, grow
I grew more and more certain that she was lying to me.

make
Make certain that you lock the door if you go out.

very
absolutely, quite
by no means
It's by no means certain that she'll get the job.

almost, virtually
fairly, pretty, reasonably

about, of
Are you quite certain about this?

can't say for certain
I think she's a teacher, but I couldn't say for certain.

not know for certain
I don't know for certain how many people are coming.

Certain is used with these nouns:
ambiguity, amount, aspect, circumstance, context, death, degree, disaster, distance, doom, exception, fascination, fondness, individual, instance, kind, mystery, number, proportion, relief, requirement, reservation, respect, sense, similarity, standard, style, type, unease