Sentence:  Her day starts early , but no matter how many pressing letters there are to be written ( and during May , which is National Salvation Army Week , there are plenty ) , schedules to be made or problems to be solved , Mrs. Marr 's office <WSD>is</WSD> always open and the welcome mat is out . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)