0 caused by a virus -- 病毒病,病毒性疾病;病毒感染
viral infections 病毒感染
1 used to describe something that quickly becomes very popular or well known by being published on the internet or sent from person to person by email, phone, etc. -- (通過網路在個體之間迅速)病毒式的(傳播)
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
再长的路,一步步也能走完,再短的路,不迈开双脚也无法到达。