Sentence:  On my first Guy Fawkes Day here , I found Catholics as well as non Catholics celebrating with the traditional fireworks and bonfires , and was told that most Englishmen either do not know or <WSD>are</WSD> not concerned with the historical significance of the day . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)