Hi, this im my first participation, and i'm very happy to join you.
My question is about this sentence.
"Air travel paralyzed as volcanic ash cloud lingers"
This is not a sentence. It's a news headline. These are not written in sentences. You might find the same thing happens in your language.
what i know that we put "is" or "was", "has been" or had been" before the verb "paralyzed".
You would in a proper sentence.