This is the 711th most frequent Lithuanian word.
koronavirusas
Coronavirus.
In this sentence, 'koronavirusas' is used as the subject of the sentence, referring to the virus itself.
Koronavirusas plinta daugelyje šalių.
The coronavirus is spreading in many countries.
Here, 'koronaviruso' is in the genitive case, indicating possession or relationship.
Žmonės nerimauja dėl koronaviruso poveikio.
People are worried about the effects of the coronavirus.
In this instance, 'koronavirusu' is in the instrumental case, used to express means or agency.