General:
* The doctor used a swab to collect a sample of the child's throat.
* I used a cotton swab to clean the delicate jewelry.
* The scientist swabbed the petri dish with a sterile cotton swab.
Figurative:
* The politician swabbed the room for votes, shaking hands and promising everything under the sun.
* She swabbed the internet for information on her new hobby.
Informal:
* I need a swab for my ear.
* He swabbed the counter with a damp cloth.
Do you have a specific context in mind for the sentence you're trying to write? I can provide more examples if you tell me what you are writing about.